Physiological effects of thyroid hormones and the mechanism of their development. Thyroid hormone: the mechanism of development and physiological effects of the medical science of thyroid hormone

It is laid out in two parts, an isthmus, and is laid out in front of the larynx. masa thyroid gland stand 30 m

The main structural and functional unit of the foliage is the rounded empty, the wall of which is approved by one row of cakes of the cubic food. Follicles with coloids and hormones thyroxineі triiodothyronine, Yaki tied with white thyroglobulin. In the mid-follicular space there is a C-cell, which is a hormone thyrocalcitonin. The zaliza is equipped with blood-bearing and lymphatic vessels. The amount that passes through the thyroid gland in 1 min, in 3-7 times the growth of the mass of the gall.

Biosynthesis of thyroxine and triiodothyronine Wishing to get rid of the amino acid tyrosine iodine, so that in the thyroid zone you will be more actively chasing iodine. Instead of iodine in the follicles, the concentration in the blood is 30 times higher, and in case of hyperfunctioning of the thyroid gland, the rate of sleep becomes even more. Praying to iodine zd_ysnyuєtsya for active transport rakhunok. Send tyrosine to enter thyroglobulin before the store, monoiodothyrosine and diiodotyrosine are set up with atomic iodine. For the preparation of two molecules of diiodotyrosine, tetraiodothyronin, or thyroxine, are established; Condensation of mono- and diiodothyrosine to produce triiodothyrosine. As a result, the result is a series of proteases, which release thyroglobulin, and bring active hormones into the blood.

The activity of thyroxine is less than that of triiodothyronine, the activity of thyroxine in the blood is approximately 20 times more, less than triiodothyronine. Thyroxine can be converted into triiodothyronin when deiodinated. On the basis of these facts, it is assumed that the main hormone of the thyroid gland is triiodothyronin, and thyroxine is the function of the thyroid mediator.

Synthesis of hormones in a non-vivid way of dressing with nadhodzhennyam in the body of iodine. Even in the region living in water and soil є deficiency in iodine, there is little yogo in the food products of the herb and foodstuffs. In general, in order to ensure sufficient synthesis of the hormone, thyroid gland of children and grown-ups grow in size, sometimes even more often, so that there is a goiter. The increase may be not only compensatory, or pathological, it is called endemic goiter. The lack of iodine in the food races is best compensated for by sea cabbage and other seafood, iodine silt, table mineral water, to expose iodine, bakery virobi with iodine additives. However, there is an overwhelming need for iodine in the organism of the targeting on the thyroid gland and can lead to severe inheritances.

Thyroid hormone

Effective thyroxine and triiodothyronine

Basic:

• activate the genetic apparatus of cellini, stimulate the exchange of words, the shedding of acidity and the intensity of oxidative processes

metabolic:

• bilkovy exchange: stimulate the synthesis of bilka, albeit at times, if the hormones change the norm, overgrowing catabolism;
• fat metabolism: stimulate lipolysis;
• in carbohydrate metabolism: in case of hyperproduction, stimulate glycogenolysis, increase blood glucose levels, activate and work properly in the middle of clitin, activate liver insulinase

functional:

• to ensure the development and differentiation of fabrics, especially nervous ones;
• to enhance the effect of a sympathetic nervous system for the development of adrenergic receptors and rotten monoaminooxidase;
• prosympathetic efficacy manifests itself in an increased frequency of heart rate, systolic volume, arterial vise, Frequency of reaction, intestinal peristalsis, anxiety of the central nervous system, increased temperature

Show changes in thyroxine and triiodothyronine products

Corresponding characteristic of the lack of production of somatotropin and thyroxine

Infusion of hormones into the thyroid gland on the function of the body

Characteristic of thyroid hormone hormones (thyroxine and triiodothyronine) is the improvement of energetic metabolism. Introduced in the supervisor of health benefits, and in the reduction of the thyroid gland. With the introduction of the hormone, the exchange of words increases, the number of energy increases, the temperature of the body rises.

Thyroxin pidsilyuє vitracannya. There is a thinning and intensive tissue recovery of glucose from blood. The drop in glucose from the blood is brought about by the successors for the increase in the amount of glucose in the blood. The reserves of lipids in the oven decrease, the amount of cholesterol in the blood decreases. It improves the vitality of water, calcium and phosphorus.

Thyroid hormones are affected by the effects of anxiety, irritability, lack of sleep, emotional neurological importance.

Thyroxin is increased in blood volume and the frequency of the heart is very fast. Thyroid hormone is necessary for ovulation, wine preservation of vaginosity, regulating the function of lactic acidosis.

Growth and development of the body is also regulated by the thyroid gland: a decrease in the function of growth. Thyroid hormone stimulates blood, increased secretion of the slunk, intestines and milk secretion.

Krim of iodine hormones, in the thyroid zone, to establish thyrocalcitonin, I reduce the amount of calcium in the blood. Thyrocalcitonin is an antagonist of parathyroid hormone in parathyroid vines. Thyrocalcitonin on cyst tissue, increasing the activity of osteoblasts and processes of mineralization. In nirkas and intestines, the hormone drives calcium reabsorption and stimulates the absorption of phosphates. Realization of cich effects to produce up to hypocalcemia.

Hyper- and hypofunction of zalozi

hyperfunction (Hyperthyroidism) serve as a cause of ill-health, invited based on ailment. The main symptoms of congestion: goiter, vitrioliness, increased frequency of speech, frequency of heart rate, increase in puffiness, moaning activity (meticulousness), disposition (dullness, moodiness, energy consumption) The goiter pretends to be a diffuse enlargement of the thyroid gland. Infection of the methods of treatment is effective, but it is important to get sick of getting sick.

hypofunction (Hypothyroidism) thyroid zalozi, scho vinikє in early vіtsі, Up to 3-4 years, symptoms development cretinism. Children who suffer from cretinism show physical and rose development. Symptoms of discomfort: dwarf growth and deterioration of proportions, wide, wide-spreading, wide-spreading eyes, open mouth and constantly hanging language, so as it is not healthy in the mouth, short The triviality of the life of such people does not change for 30-40 years. In the first 2-3 months of life, you can ask for a little normal psycho development... If you like to fix up in a one-time business, then 40% of children, who have become aware of a sickness, fall into an even lower level of mental development.

Hypofunction of the thyroid gland in the grown-ups should be brought to the diagnosis miksedemoyu, abo muddy stuff. At the same time, there is a decrease in the intensity of exchange processes (by 15-40%), the temperature of the body, the pulse grows older, the arterial grip decreases, there is swelling, it looks like hair, it doesn’t lame, the person grows dead. People who are sick become sleepy, sleepy, and a rotten memory. Miksedema is more and more progressively ill, as when it is out of sight, it can be brought to an end.

Regulation of the function of the thyroid gland

A specific regulator of thyroid activity is iodine, the thyroid hormone itself and TSH (thyroid stimulating hormone). Iodine in small doses increases the secretion of TSH, and in large doses it increases the secretion. The thyroid gland is found under the control of the central nervous system. Such food products, yak cabbage, brookva, turnips, are used to adapt the function of the thyroid gland. Vyrolennya thyroxine and triiodothyronine will live up to the minds of trivial emotional energy. It is also meant that the secretion of hormones is quickened when the temperature is low.

Manifest damage to the endocrine function of the thyroid gland

With advanced functional activity of the thyroid gland and overworld production of thyroid hormones in the winery hyperthyroidism (hyperthyroidism), It is characterized by changes in the blood of thyroid hormones. I will begin to be explained by the effects of the third hormones in the incremental concentrations. So, through the adjustment of the main exchange (hypermetabolism) in the sick small advices temperature (hyperthermia). Change masa tila do not marvel at savings or changes in appetite. Tsei stan is manifested in the increase in consumption, tachycardia, in the rapidity of the myocardium, in the increase in systolic arterial vise, in the increase in ventilation legends. The activity of the ATP is increasing, the number of p-adrenorecentors is increasing, the energy and heat intolerance are developing. There is an increase in wakefulness and emotional lability, there may be a tremor of symptoms and changes in the body.

The adjustment and secretion of thyroid hormones have been determined by a number of factors, such as the correct detection of thyroid hormones by the method of correcting the function of the thyroid gland. Among them are factors that affect the hyperfunction of the follicular cells of the thyroid gland (swelling of the gall, mutation of G-bile) and the development of education and secretion of thyroid hormones. Hyperfunction of thyrocytes is susceptible to overwhelming stimulation of thyrotropin receptors caused by TSH, for example, in case of puffiness of the hypophysis, or a decrease in the sensitivity of the receptors of thyroid hormones. often the reason hyperfunction of thyrocytes, an increase in the size of the growth and stimulation of the TSH receptors by antibodies, violated to them in case of autoimmune disease, called Graves' - Basedov's ailment (Fig. 1). Timing of the increase in the level of thyroid hormones in the blood can develop when the thyrocytes are ruined in some cases ignition processes in the zone (toxic Hashimoto's thyroiditis), taking overworldly levels of thyroid hormones and iodine preparations.

Adjustment of thyroid hormone levels can be manifested thyrotoxicosis; in general, talk about hyperthyroidism with thyrotoxicosis. Ale thyrotoxicosis can develop when superfluous thyroid hormones are introduced into the body, for hyperthyroidism during the day. The development of thyrotoxicosis is described as a result of the increase in the sensitivity of receptors of clitin to thyroid hormones. As a result of antibiotics, if the sensitivity of the clin to thyroid hormones is reduced and the resistance to thyroid hormones develops.

Decrease in the education and secretion of thyroid hormones can be reduced for no reason, some of them are partially damaged by the mechanism of regulation of the function of the thyroid gland. So, hypothyroidism (hypothyroidism) It can be developed with a decrease in the level of TRG in the hypothalamus (chickens, bristles, optimization, encephalitis in the area of ​​the hypothalamus and in.). Such hypothyroidism is called tretiny. Secondary hypothyroidism develops as a result of insufficient coverage of THG with hypophysis (puffiness, bruises, abnormalities, surgical parts of the hypophysis, encephalitis and inn.). Primary hypothyroidism can develop in cases of autoimmune inflammation of the disease, in case of deficiency of iodine, selenium, inappropriately overwhelming intake of plant-derived products - goitrogens (varieties of cabbage), food production, trifle disease

Small. 1. diffuse zbіlshennya Thyroid growths in a 12-year-old girl with autoimmune thyroiditis (T. Foli, 2002)

Lack of production of thyroid hormones to reduce the intensity of metabolism, recovery of sourness, ventilation, rapidity of myocardium and blood volume. With an important hypothyroidism, the camp may develop, but I will name it myxedema- slime block. Wine is developed through accumulation (it is possible to pour in p_vischenogo rivnya TTG) mucopolisaccharides and water in the basal balls of the shkiri, so that the individual and the thick-like consistency of the shkiri can be inflated, as well as to increase the mass, without affecting the decrease in appetite. In people with miksedemoyu can develop psychotic and rukhovy, drowsiness, frostiness, decrease in intellect, tone nice to see ANS and іnshi changes.

In the healthy folding processes of the establishment of thyroid hormones, the role of the pump is taking over, so that the proper iodine, a number of enzymes of a protein nature, among the key role in the development of thyroid peroxidase, are not needed. In a number of individuals in humans, there may be a genetic defect, which leads to a breakdown in their structure and function, which leads to a breakdown in the synthesis of thyroid hormones. You can sposter genetic defects in the structure of thyroglobulin. Against thyroperoxidase and thyroglobulin, autoantitila is not easily violated, which also leads to impaired synthesis of hormones in the thyroid gland. On the activity of the processes of accumulation of iodine and its inclusion in the storage of thyroglobulin, it is possible to infuse a number of pharmacological conditions, regulating the synthesis of hormones. Pa їkh synthesis can be infused with iodine preparation.

The development of hypothyroidism in the fetus and newborns should not be brought before cretinism - physical (maliy spist, destructive proportions of til), statical and rosy underreported. Changes can be remembered when adequate therapy with thyroid hormones is carried out in the first month of the life of the child.

Budova thyroid gland

Є for its own mass and size of the most endocrine organ. You want to fold in two parts, with a single isthmus, and grow on the front surface of the shoulder, being fixed to the front and side surfaces of the trachea and larynx with good cloth... The middle vaga of a normal thyroid nodule in adults grows in the boundaries of 15-30 g, protean growth, the form and topography of the growth are widely varied.

The functionally active thyroid lobe of the first endocrine loom appears in the process of membrane genesis. The laying of the thyroid gland in the human fetus is formed on the 16-17th day intrauterine development at the viglyad there is a purchase of entodermal cells for the root of the tongue.

At the early stages of development (6-8 types), the rudiment of the formation is a layer of intensively proliferating epithelial cells. In the whole period of time, it’s growing up, but not yet hormones. The first signs of this secretion appear on the 10-11th pressure (in the fruit, the size is close to 7 cm), if the cells have already gnawed the iodine, they make the coloids and synthesize thyroxine.

From the capsule there are single follicles, in which follicular cells are formed.

In the rudiment of the thyroid gland, from the 5th paris of the chickweed, the colonies grow parafollicular (near-follicular), or C-clitini. Until the 12-14th period, the whole fruit growth the rights of the part the thyroid gland of the follicular budova, and the liva - two times more. Until the 16-17th thyroid gland, the fetus is already differentiated. The thyroid nests of fruits of the 21-32th type are characterized by a high functional activity, as they prodovzhu growths up to 33-35 types.

In parenchymal cells, three types of cells are developed: A, B and C. The main mass of cells in parenchyma is stored in thyrocytes (follicular, or A-cells). The stench whistles a stack of foliage, in the empty spaces there are coloids. The dermal follicle of exudation is a thick net of capillaries, in the lumen of which the thyroxin and triiodothyronin are secreted by the thyroid gland.

In nezmenenii thyroid zalozi follicles are equal to the growth of all parenchyma. With low functional activity, the thyrocytes are usually flat, with high - cylindrical (the height of the cells is proportional to the level of activity of the processes in them). The coloid, which will memorize the enlightenment of the follicles, is a homogeneous tie of ridin. The main mass of coloids is to form thyroglobulin, secretion of thyrocytes into the follicle enlightenment.

In-cells (cells Ashkenazi - Gyurtlya) are larger than thyrocytes, may eosinophilic cytoplasm and a rounded centrally expanded nucleus. In the cytoplasm of cytoplasm, the cytoplasm contains biogenic amino acids, including serotonin. For the first time, V-klіtini z'yavayutsya at 14-16 years old. The great number of stinks is produced in people at 50-60 years of age.

Parafollicular, or C-clytini (in the Ukrainian transcript C-clytini), is seen as thyrocytes from the outside of the body and iodine. The stench will start the synthesis of calcitonin - a hormone, which will take part in the regulation of calcium metabolism in the body. There are three cells of large thyrocytes in the warehouse of follicles of rosters, as a rule, one at a time. Їх morphology is typical for cells, which synthesize blocks for export (the presence of a short cut endoplasmic mesh, Golgi complex, secretory granules, mitochondria). On histological preparations, the cytoplasm of C-clitin is lighter in the cytoplasm of thyrocytes;

Although on a tissue ryvnі of the main structural and functional unit of the thyroid gland є follicles, otchin with basal membranes, then one of the organ organs of the thyroid gland can be small, enter the folds of the hemophilia Up to the microblood warehouse there are 4-6 follicles, separated by a membrane of fibroblasts.

Until the moment of population, the thyroid gland is functionally active and structurally completely differentiated. In newborns, the follicles are dibni (with a diameter of 60-70 microns), in the world the development of a child's body and their size grows and reach in adults of 250 microns. In the first, two types of folk follicles develop intensively, up to 6 months of stench of good growth in all salmon, and up to the rock they reach a diameter of 100 microns. In the period of statutory maturity, it is meant to strengthen the growth of parenchyma and stroma zolosis, to increase the functional activity, to increase the amount of thyrocytes, to increase the activity of enzymes in them.

In the growth of a human, the thyroid gland is prone to the larynx and the upper part of the trachea in such a rank that the isthmus grows on the level of II-IV tracheal spines.

Masa and the growth of the thyroid gland with a stretch of life change. In a healthy new-born mass, it grows from 1.5 to 2 m. Until the end of the first fate of life, the mass grows up and grows up to the period of the state maturation of up to 10-14 m. Masa of the thyroid gland at the site of 20-60 rocky ranges from 17 to 40 m

The thyroid gland can be reduced to blood circulation in the porous organs. The volume of blood flow in the thyroid gland becomes close to 5 ml / g in quiline.

Thyroid gland with blood paired upper and lower thyroid arteries. Inodi in bloodsucking the fate is unpaired, the lower artery itself (a. thyroideaima).

The appearance of venous blood from the thyroid gland rises through the veins, as well as gossip in the circumference of the biches and the isthmus. The thyroid gland grows thin on the edge of lymphatic vessels, according to which lymphs are detected in high lymphatic universities, at the same time in the supraclavicular and lateral high lymphatic nodes. Grape lymph vessels of the lateral lumbar gliboids lymphatic universities set on the skin side of the jugular stovbur, which flows into the thoracic duct, and the right-handed person - into the right lymph duct.

The thyroid gland is innervated by the postganglionic fibers of the sympathetic nervous system from the upper, middle (head rank) and lower sheeh nodes of the sympathetic stovbur. The thyroid nerves make gossip about the suckers, so that they can go to the shanks. Vvazhayut, scho tsі nerves vikonuyut vasomotor function. In the innervation of the thyroid gland, the fate of the erosive nerve, which does not carry parasympathetic fibers before being buried in the storage of the upper and lower laryngeal nerves... The synthesis of iodine hormones in the thyroid gland T3 and T4 is developed by follicular A-cells - thyrocytamines. Hormones T 3 і T 4 є iodovanim.

The hormones T4 and T3 are iodinated with the amino acid L-tyrosine. Iodine, which is included in the structure, becomes 59-65% of the hormone molecule mass. The requirement for iodine for the normal synthesis of thyroid hormones is presented in table. 1. The sequence of the synthesis processes is simplified to be presented in such a way. Iodine in the form of iodide is consumed from the blood behind an additional ion pump, accumulates in thyrocytes, oxidizes and is included in the phenolic ring of tyrosine in the storage of thyroglobulin (organopharmaceutical iodine). Iodization of thyroglobulin from the statements of mono- and diiodothyrosis is carried out on the cordon of thyrocytes and coloids. How long does it take to get (condensation) of two molecules of diiodothyrosine in the formulation of T 4, or diiodotyrosine and monoiodothyrosine in the formulation of T 3. Part of the thyroxin goes into the thyroxine zone of the deionisation.

Table 1. Standards for the living of iodine (BOOZ, 2005. According to I. Didiv and Spivavt. 2007)

Iodine thyroglobulin at the same time with the addition of up to new T 4 and T 3 accumulate and accumulate in the follicles at the viglyadi coloids, which play the role of depot thyroid hormones. The development of hormones in the result of pinocytosis of the follicular coloids and the additional hydrolysis of thyroglobulin in phagolisosomes. Vivilny T 4 and T 3 are secreted into the blood.

Basal additional secretion of the thyroid gland is close to 80 mcg T 4 and 4 mcg T 3 With a large thyroid follicle of the thyroid gland with a single dzherel the establishment of endogenous T 4. form the hormone to work in the cells of all tissues of the body, the deiodination rate is close to 80% T 4.

In such a rank, the extra-glandular depot of thyroid hormones in the body є the other is the extra-glandular depot of thyroid hormones, represented by hormones tied with transport blood cells. The role of the cich depot polyagus in the reduction of the level of thyroid hormones in the organism, as could have happened with a short-hour reduction in the synthesis, for example, with an uncommon reduction in the level of iodine in the organism. tied the form hormones in the blood of the hormones in the body through the nirks, the capture of the cells because of the uncontrolled need for hormones in them. In a cell, one needs to supply hormones in quantities appropriate for their functional needs.

Thyroxine, when it comes to cells, is deiodinated under the influence of deiodinase enzymes, and when one atom of iodine is added, a larger active hormone, triiodothyronin, is released. At the same time, in the presence of deionized paths from T 4, both active T3 and inactive reversible T3 (3.3 ", 5" -triiod-L-thyronin - pT 3) can be established. The hormones by the way of the last deiodination are converted to the metabolism of T 2, then T 1 and T 0, which conjugate with glucuronic acid or sulphate in the liver, and are transported from the gum and through the organisms. Not only T 3, but also the metabolism of thyroxine can also show biological activity.

Mechanism of the development of third hormones perch for all interactions with nuclear receptors, such as non-stony cells, which take place without the middle in the nuclei of the clitin. There are three main types of receptors for thyroid hormones: TPβ-2, TPβ-1 and tra-1. As a result of the interaction with the T 3 receptor, the hormone-receptor complex enters into interaction with the hormone-sensitive DNA and regulates the transcriptional activity of the gene.

A number of non-genomic effects of the third hormones have been revealed in the mitochondria, the plasma membrane of the clitin. Drops, thyroid hormones can reduce the penetration of mitochondrial membranes for protons in water, and the processes of energy and phosphorylation, reduce the synthesis of ATP and increase the heat in the body. The stench changes the penetration of plasma membranes for Ca 2+ ions and is infused into rich internal processes, thanks to the participation of calcium.

Basic Effects and the Role of Thyroid Hormones

Normal functioning of all organs and tissues without blame is possible with normal levels of thyroid hormones, so as a stench is injected on the growth and dosage of tissues, energy consumption and exchange of nuclei, acids See the metabolic and physiological effects of thyroid hormones.

Metabolic effects:

• activation of oxidation processes and improvement of the main exchange, improvement of the drying process by fabrics, adjustment of heat dissipation and temperature;
• stimulation of protein synthesis (anabolism) in physiological concentrations;
• strengthening of oxidized fatty acids і lowering їх level in blood;
• hyperglycemia for activation of glycogenolysis in oven.

Physiological Effects:

• securing normal growth processes, development, differentiation of cells, tissues and organs, including the central nervous system (myelination of nerve fibers, differentiation of neurons), as well as processes of physiological tissue regeneration;
• improvement of the SNS effects through the adjustment of the sensitivity of adrenergic receptors to the adr and NA;
• alarming of the central nervous system and activation of mental processes;
• the fate of the unhealthy reproductive function (the synthesis of GH, FSH, LH and the implementation of the effects of the insulin-like growth factor - IFR);
• the fate of the formulated adaptive reactions to the body to unpleasant infusions, zokrem, cold;
• the fate of the development myazovoy system, The increase in strength and quality of meat is very fast.

Regulation of education, secretion and re-transformation of thyroid hormones work by folding hormonal, nervous and other mechanisms. The knowledge allows the diagnosis of the cause of the decrease or the adjustment of the secretion of thyroid hormones.

The key role in the regulation of the secretion of thyroid hormones is played by the hormones of the hypothalamic-hypophyseal-thyroid axis (Fig. 2). The basal secretion of thyroid hormones and changes during inflows is regulated by the TRH of the hypothalamus and the TSH of the hypophysis. TRG stimulates the production of TTG, which is a stimulating infusion practically on all processes in the thyroid hall and secretion of T 4 and T 3. In normal physiological minds, the development of TRG and TTG is controlled by the blood and blood pressure of T. 4. ... With a wide secretion of TRH and TSH, it is driven by a high level of thyroid hormones in the blood, and with a low concentration, it increases.

Small. 2. Schematic representation of the regulation of education and secretion of gypsum in the axis of hypothalamus - hypophysis - thyroid gland

More important in the mechanisms of regulation of hormones of the hypothalamic-hypophyseal-thyroid axis is the sensitivity of the receptors to the hormones on the young wasps. Changes in the structure of their receptors or stimulation by autoantibodies can be the reasons for the impairment of the hormones in the thyroid gland.

Osvita hormones in the most zlozi to lay aside the necessary amount of iodide in her blood - 1-2 μg per 1 kg of oil (Div. Fig. 2).

With a lack of adequate iodine in the body, adaptive processes develop in a new way, which are straightened at the maximum possible size and efficiency, which is evident in new iodine. Stinks in the blood flow through the bloodstream, more efficiently absorbed by iodine in the thyroid zone from the blood, changes in the processes of hormone synthesis and secretion of the Tu. If you do not need the necessary iodine in the body to become less than 20 mcg for a trivial hour, then the stimulation of the thyroid clit is trivial until the growth of the tissue and the development of the goiter.

Self-regulatory mechanisms of iodine deficiency in minds will prevent more thyrocyte accumulation in case of a higher low level of iodine in the blood and more effective reutilization. As soon as it is delivered to the body for up to 50 mcg of iodine, then for the preparation of the growth of blood thyrocytes from the blood (iodine of grub and reutilization of iodine from the products of metabolism) in the thyroid close to the lining of the suprahydrocyte 100 mcg.

Adequacy of the slunk-intestinal tract of 50 mcg of iodine at an additional threshold, when there is still a triviality of the thyroid gland accumulation of iodine (including reutilization of iodine) in quantities, if there is too little interorganic iodine. The lower threshold for iodine in the body for the addition, the efficiency of the growth of iodine by the thyroid gland appears to be a deficiency, the grip of iodine and the wickedness in the zalose to change. In cich vipadkakh of development, the function of the thyroid gland becomes more imovirny.

Immediately, with the inclusion of adaptive mechanisms of the thyroid gland in case of iodine deficiency, a decrease in the efficiency of the organism with the cut is prevented. As a result of adaptations of secretory mechanisms, there is no need to transfer iodine to the body for the addition of iodine in quantities that are equivalent to a greater low additional need for the intestinal tract.

Adequacy in the organism of sub-threshold concentrations of iodine (less than 50 mcg per dose) leads to an increase in TSH secretion and stimulating infusion into the thyroid gland. The price for supernatant growth is the accelerated iodination of thyroglobulin thyrozyl surpluses, the increase in the substitution of monoiodinroses (МІТ) and decreases in the amount of diiodinosis (DIT). The stage of МІТ / ДІТ grows, and, as a legacy, the synthesis of T4 changes and the synthesis of T 3. The stage of T 3 / T 4 grows in the hall and blood.

With an increased iodine deficiency, there is a decrease in the decrease in the level of T 4, the increase in the level of TTG is normal, for the change in the T 3. spіvvіdnoshennya T 3 T 4 і improvement of T 4 in T 3 in peripheral tissues.

The improvement in the coverage of T3 in the minds of iodine deficiency is justified from the point of view of the achievement of the greatest endometabolic effects of TG in the case of the smallest "iodine" capacity. Seemingly, if the T 3 metabolism is injected into the metabolism of T 3 by about 3-8 times stronger, lower than T 4, or if T 3 takes away 3 atoms of iodine from its structure (and not 4 atoms of T 4), then for the synthesis of one T 3 molecule it is required only 75% of iodine vitrates, in the case of synthesis of T 4.

With a strongly significant iodine deficiency and decreased function of the thyroid gland on aphids of the high level of TTG, the level of T 4 and T 3 decreases. In syrovatz blood, there is more thyroglobulin, the level of which is the core of the level of TTG.

Iodine deficiency in children is more pronounced, less in older adults it is infused into the metabolic processes in the thyrocytes of the thyroid gland. In iodine-deficient areas, the deterioration of the thyroid function in newborns and children occurs more often and more often, less in older adults.

If there is a small excess of iodine in the organism of a person, the steps of organopharmaceutical iodide, the synthesis of TG and its secretion will be accepted. The increase in the value of TTG is evident, the decrease in the level of T 4 in syrovatz is not large, with an one-hour change in thyroglobulin. A greater excess of iodine recovery can block the synthesis of TG for the reduction of the activity of enzymes involved in biosynthetic processes. Even before the end of the first month, the increase in thyroid growth is indicated. With chronic overwhelming superfluous iodine in the body, hypothyroidism can develop, if iodine is more likely to normalize in the body, then the growth and function of the thyroid gland can turn to cob values.

Dzherelami iodine, which can be the cause of the overwhelming need in the body, often є iodine strength, complex polyvitamin preparations, which revenge mineral additives, food products and deyakі iodine drinks.

The thyroid gland has an internal regulating mechanism, which allows to efficiently cope with the overwhelming necessary iodine. If you want the necessary iodine to enter the body, the concentration of TG and TSH in the blood can become unimportant.

It is important that the maximum amount of iodine is maximal, as if the body does not have any changes in the function of the thyroid gland, it should be for older adults close to 500 mcg per day, but at the same time it is more difficult to increase the level of energy consumption.

Adequate iodine in amounts of 1.5-4.5 mg per day should be brought to a significant change instead of in syrovattsi, as a zagalny so і vіlny T 4, increase the level of TTG (rіven T 3 become unimportant).

The effect of suppressing too much iodine in the function of the thyroid gland is miserable and in case of thyrotoxicosis, if the intake of an overwhelming amount of iodine (in relation to the natural good intake) is assimilated symptoms of thyrotoxicosis in the course of thyrotoxicosis. However, when there is a trivial overload of iodine in the body, thyrotoxicosis will turn again. Vvazhayut, that the time of the decrease in the level of TG in the blood with overwhelming necessary iodine is poured over for all the secretion of hormones.

Nadkhozhennya in the organism of small oversized quantities of iodine to the proportional reduction of its drowning with a thyroid zone, to the point where it is important to bow to iodine. When the value of iodine is accumulated with zolozuyu can change unimportantly to the good of it in organism in great numbers. In cich umovah, under the inflow of TSH hypophysis, the activity of the thyroid zone can change in wide fringes.

Oskilki, when necessary in the organism of excess iodine, the level of TSH grows, then it will not ochikuvati not cob stifling, but the activation of the function of the thyroid gland. However, it has been established that iodine induces an increase in the activity of adenylate cyclase, induces the synthesis of thyroperoxidase, which induces hydrogen peroxide in the presence of TTG, I want to trigger the membrane of TTG from the receptor.

It also meant that the function of the thyroid gland was driven too much of the iodine to have a time-consuming character, and the function was unimportant to introduce unimportant amounts of iodine into the body. Adaptation infusion or the escape of the thyroid gland with iodine injected. One of the main mechanisms of adaptation is the reduction of the efficiency of storage and the transport of iodine to the trocyte. Oskilki vvazhayut, so the transport of iodine through the basal membrane of the thyrocyte dressings with the function of Na + / K + ATP-asi, then it is possible to ochikuvati, so an excess of iodine can be infused on the її power.

Unimportant on the mechanism of adaptation of the thyroid gland to the lack of abnormally overwhelming entrance to iodine for the sake of saving normal function iodine balance is guilty in organism. With a normal level of iodine in the ground and water, for adding to the human organism with the tall grass and in the small world with water, up to 500 μg of iodine in the form of iodide or iodate can be added, as it is converted into iodide into the slurry. Yodidi quickly get wet from the shlunkovo-intestinal tract and grow into the postoperative body. The concentration of iodide in the back spaces becomes too low, as a part of the iodide is thirsty for a post-clotted line of thyroid gland, and when it is overshadowed, it is lost to the body at night. The fluidity of the iodine entrapped by the thyroid gland is wrapped in proportion to the fluidity of the iodine vivedennya with nirkas. Iodine can be seen in small and small vines herbal tract, Ale then, I know to reabsorb from the intestines into the shelter. Closely 1-2% of iodine is secreted by sweaty vines, and when it is possible to see it, a fraction of iodine can be seen with iodine as high as 10%.

With 500 mcg of iodine, which is moistened from the upper intestines into the roof, about 115 mcg will be consumed by the thyroid gland, and about 75 mcg of iodine will be added to the synthesis of TG, 40 mcg should be turned back in the position of ridin. Synthesized T 4 and T 3 run in a wide range of ovens and other tissues, with a total amount of iodine in a quantity of 60 mcg consumed in the roof and after a period of time, and close to 15 mcg of iodine, which is conjugated in sulphurous aminhoids, with ...

In the out-of-town community, there is a pozaklitinna rіdina, yak to become close to 35% of the mass of people (or close to 25 liters), in which it is close to 150 mcg of iodine. Iodide can be easily filtered in the glomeruli and approximately 70% passively reabsorbed in the tubules. For the addition of close to 485 μg of iodine, it is introduced into the organism with the cross section and approximately 15 μg - with the feces. The average concentration of iodine in the blood plasma is detected at a level close to 0.3 μg / l.

With a decrease in the necessary iodine in the body, the decrease in the number in the depths of the body, the decrease in the thickness of the cross section, and the thyroid gland can increase in the amount of bowel movement by 80-90%. The thyroid gland is a great store of iodine in the form of iodothyronin and iodinated tyrosine in quantities close to 100-day consumption by the body. For the release of cychological iodine-free mechanisms and deposited with iodine, the synthesis of TG in the sinks of the deficiency of the necessary iodine in the body can become unimportant for a period of one hour to two months. Greater iodine deficiency in organisms before lowering the synthesis of TG is unimportant to the maximum concentration of blood in the blood. Improving the iodine organism can accelerate the synthesis of TG. However, iodine replenishment has overwhelmed 2000 mcg, accumulated iodine in the thyroid gland reaches the level, if iodine accumulation and hormone biosynthesis are inhibited. Chronic iodine poisoning of the vine, since it is more likely to be in the body 20 times more than necessary.

An entrant into the organism of iodide is the head rank of the cross, that is, it’s a great deal in general, the best indicator of the appropriateness of iodine and can be used to assess the iodine balance in the central body.

Thus, a sufficient supply of exogenous iodine is necessary for the synthesis of TG in quantities adequate to the needs of the body. At the same time, it is normal for the implementation of TG effects to accumulate in the form of efficiency of linking with nuclear receptors of kinin, before the warehouse of which includes zinc. Also, the hope for the organism of a sufficient amount of microelement (15 mg / dob) is also important for the manifestation of TG effects on the cell nucleus.

Osvita in peripheral tissues of active forms of TG with thyroxin is taken before deiodinases, for the manifestation of activity, the presence of selenium is necessary. It was established that selenium in amounts of 55-70 mcg per day is necessary for the organism of the growth of humans and selenium is necessary for the establishment in the peripheral tissues of a sufficient amount of T v

The nerves of the mechanisms of regulation of the function of the thyroid gland are healed through the inflow of neuromediators of the ATP and the PSNS. SNS innervates with its post-ganglionic fibers the skin of the glandular tissue. Norepinephrine pushes the level of cAMP in thyrocytes, stimulates them with iodine, synthesis and secretion of thyroid hormones. The fibers of the PSNS can also reach the follicles and vessels of the thyroid gland. An increase in the tone of the PSNS (or the introduction of acetylcholine) is supervised to increase the level of cGMP in thyrocytes and a decrease in the secretion of thyroid hormones.

Under the control of the central nervous system, there is an overview of the secretion of TRH by intracellular neurons of the hypothalamus, as well as the secretion of TSH and hormones in the thyroid gland.

The level of thyroid hormones in the cells of tissues, their transformation in the active form and metabolism is regulated by the system of deiodinases - enzymes, the activity of which lies in the presence of selenocysteine ​​in cells and the reliability in the body. Є three types of deiodinases (D1, D2, DZ), which are differently developed in the other tissues of the body and start the transfer of thyroxine into active T3, or inactive pT 3 and other metabolites.

Endocrine function of parafolicular K-cells of the thyroid zone

Cyclinis synthesize and secrete the hormone calcitonin.

Calcitonin (tireocalcitioin)- a peptide that can accumulate from 32 amino acid surpluses, instead of at the blood level, it becomes 5-28 pmol / l, for cells of a target, stimulating T-TMS-membrane receptors and producing cAMP and IPH levels in them. It can be synthesized in thymus, legends, central nervous system and other organs. The role of extrathyroid calcitonin in nevdom.

The physiological role of calcitonin is the regulation of the level of calcium (Ca 2+) and phosphates (PO 3 4 -) in the blood. The function is implemented for the development of decile mechanisms:

• rotting of functional activity of osteoclasts and suppression of resorption knitted fabric... Price reduction for the delivery of ions of Ca 2+ and РВ 3 4 - from the cyst tissue to the roof;
• reduction of reabsorption of ions of Ca 2+ and RV 3 4 - from the primary section in nirkovy tubules.

For rakhunok cich efects, the adjustment of the level of calcitonine to the decrease in the place of ions Ca 2 and PB 3 4 is at the blood.

Regulation of secretion of calcitonin Help for the non-mediated participation of Ca 2 in the blood, the concentration of which in the norm becomes 2.25-2.75 mmol / l (9-11 mg%). Addition of calcium in the blood (hyperscalcism) is active in the secretion of calcitonin. Decrease of the level of calcium before the decrease of the secretion of the hormone. Stimulate the secretion of catecholamine calcitonin, glucagon, gastrin and cholecystokinin.

The growth of calcitonin (in 50-5000 times in the norm) is prevented with one form of thyroid cancer (medullary carcinoma), which develops from parafolicular clitins. With a large amount of calcitonin in the blood of a high rivny, one of the markers of the disease.

Increase in blood calcitonin levels, as it is practical to increase the visibility of calcitonin in the presence of a visible thyroid gland, which may not supervise the loss of calcium and stun system systems... It is important to beware of those that the physiological role of calcitonin in the regulation of calcium should not be overlooked.

Thyroid hormones a wide range dії, ale naybіlshe їх injected to be recognized on the keratin core. The stench can be infused into the processes that flow through the mitochondria, as well as into the cell membrane.

Among the social workers and people, thyroid hormones are especially important for the development of the central nervous system and for the growth of the body as a whole.

For a long time I have been stimulating the development of hormones for the quickness of the life-cycle (caloric effect) by all organisms, as well as by tissue and subclinical fractions. Іstotnu role in mehanіzmі fіzіologіchnogo kalorіgennogo efekta T 3 T 4 i Mauger Grati stimulyatsіya such enzymatic synthesis bіlkіv, SSMSC in protsesі svogo funktsіonuvannya vikoristovuyut energіyu adenosine triphosphate (ATP), napriklad, chutlivoї to oubaіn membrannoї natrіy-kalіy-ATPase scho pereshkodzhaє vnutrіshnoklіtinnogo nakopichennya іonіv sodium. Thyroid hormones in response to adrenal and insulin membranes.

A special role is played by thyroid hormone in the regulation of function heart-vascular system... Tachycardia with thyrotoxicosis and bradycardia with hypothyroidism - characteristic signs damage to thyroid status. Tsi (so it’s very yak and a lot of them) show the disease of the thyroid gland during the last hour they were taken for the development of a sympathetic tone from the other thyroid hormones. However, in Danish hour it was brought that the overwhelming vm_st in the body to reduce the synthesis of adrenaline and norepinephrine in the supernatural and the decrease in the concentration of catecholamines in the blood. With hypothyroidism, the concentration of catecholamines in growth. We didn’t reject the confirmation and data about the suspicion of the degradation of catecholamines in the minds of the overworld instead of thyroid hormones in the body. Nayimovirnishe, for the development of a non-mediated (without the participation of adrenergic mechanisms) thyroid hormones on the tissue, the sensitivity of the rest to catecholamines and mediators of parasympathetic infusions changes. Indeed, with hypothyroidism, an increase in the number of beta-adrenergic blockers in a number of tissues is described (including in the heart).

Mechanisms of penetration of thyroid hormones into cells of vivchenia are insufficient. Necessarily because of the fact that diffusion is passive here, for active transport, and hormones penetrate into the cell "mission" to finish quickly. Mingling for T 3 and T 4 appears not only in the cytoplasm, mitochondria and nuclei, but also on the cell membrane, protects in the nuclear chromatin cells are found in the back of the interior The ratio of the types of bins to the older analogs of the T 4 evolves in proportion to the biological activity of the rest. The stage of occupation of such women is in the range of proportions and the magnitude of the clinical response to the hormone. The connection of thyroid hormones (which is importantly T3) in the nucleus is formed by non-stonic cells of chromatin, the molecular weight of which is about 50,000 daltons for solubilization. For the nuclear activity of thyroid hormones, in general, there is no need for a prior interaction with cytosol cells, as it is described for steroid hormones. The concentration of nuclear receptors is especially high in tissues that are sensitive to thyroid hormones (the anterior part of the hypophysis, liver), and is even low in the cells and on those who do not respond to 3

For the interaction of thyroid hormones with the chromatin receptors to achieve the rapid growth of the activity of RNA polymerase and to increase the acceptance of high molecular weight RNA. It has been shown that the limit of generalized injected into the genome, T3 can vibrate stimulate the synthesis of RNA, and that the determination of specific proteins, for example, alpha2-macroglobulin in the liver, hormone growth in the metabolism, fertility enzyme. With physiological concentration of hormones, the nuclear receptor is 90% higher than T 3, while T4 is present in the complex with receptors in an even smaller number. Tse vypravdovu thought about T4 yak prohormones and about T3 yak about reference thyroid hormones.

Regulation of secretion. T 4 and T 3 may not only be found in TTG hypophysis, but in some other factors, as well as in the concentration of iodide. However, the head regulator of the activity of the thyroid gland is still TSH, the secretion of which is located under subordinate control: from the side of the hypothalamic TRH and peripheral thyroid hormones. At the time of the adjustment of the concentration, the residual reaction of the TTG on the TRG is attributed. The secretion of TSH is not only affected by T 3 and T 4, but by hypothalamic factors - somatostatin and dopamine. The interaction of all these factors and the purpose is to achieve a fine physiological regulation of the thyroid function depending on the individual needs of the body.

TSH є glycopeptide s molecular weight 28,000 daltons. Wines are stored in 2 peptide lances (subunits), tied by non-covalent forces, and 15% in carbohydrates; The alpha subunit of TSH is not recognized as such in other polypeptide hormones (LH, FSH, chorionic gonadotropin). The biological activity and specificity of the TSH is accumulated in its beta-subunit, as the thyrotrophs of the hypophysis are synthesized more or less and then come to the alpha subunit. Tsya vzaєmodia vіdbuvaєtsya to finish quickly for synthesis, so as secretory granules in thyrotrophs to replace the main ready hormone. However, there is a small number of sub-units that can be seen before the TRG in an unimportant way.

The hypophyseal secretion of TSH is even sensitive to changes in the concentration of T 4 and T 3 in syrovatz blood. Reducing or increasing the concentration of concentration by 15-20% to produce reciprocal damage in the TSH secretion and its reaction to exogenous TRH. The activity of T 4 -5-deiodinase in the hypophysis is especially in the temporal area, so the syrovatous T 4 in the new one is transformed into T3 more actively, lower in the other organs. Jmovirno, the same decrease in the level of T 3 (while saving normal concentration of T 4 in syrovats), reestablished in case of important non-thyroid incapacitation, it is seldom to increase the secretion of TTG. Thyroid hormones reduce the number of TRH receptors in the hypophysis, moreover, the galvanic infusion on the TSH secretion is often blocked by the inhibitors of the protein synthesis. The maximum galmuvannya of the secretion of TTG in the wine is in a trivial hour after reaching the maximum concentration of T 4 and T 3 in syrovatz. І navpaki, Rizke Padinnya The level of thyroid hormones in order to produce a visible thyroid gland to produce an update of the basal secretion of TTG and its reaction to TRH deprivation through a few months or to see more. It is necessary to take a brother to respect when evaluating the hypophyseal-thyroid axis in ailments, so that one can get involved in the drive of a thyroid disease.

Hypothalamic stimulant of TSH secretion - thyreoliberin (pyroglutamylgistidylprolinamide tripeptide) - in the greatest concentration of the presence in the middle raised and arcuate nuclei. However, it appears in the brain, as well as in shlunkovo-intestinal tractіpankreatichesky islands, because of this function there is little vivification. It is similar to the TRH peptide hormones that are inter-modulated with the membrane receptors of the pituitary. The number of changes is not only due to thyroid hormones, but if the thyroid hormone is adjusted ("lower regulation"). Exogenous TRH stimulates the secretion of not only TSH, but prolactin, but acromegaly and chronic damage liver function і nirok - і approval of the hormone growth. However, the role of the TWG in physiological regulation secretion of hormones is not established. The hour for the exogenous TRG in Syrovattsi people to finish is small - 4-5 min. Thyroid hormones, however, are not injected into its secretion, but the problem of regulating the rest is practically non-invasive.

Krym zgaduvanny galvanic injected somatostatin and dopamine for the secretion of TSH, it is modulated by the order of steroid hormones. Thus, estrogen and oral contraceptives improve the response of TSH to TRH (possibly, for the increase in the number of TRH receptors on the membrane of the front lobe of the hypophysis), it will flank the halmic action of dopaminergic hormonal Pharmacological doses of glucocorticoids reduce the basal secretion of TSH, its reaction to TRH and for the first time in the evening of the day. However, the physiological significance of all the modulators of the TSH secretion is unavoidable.

Thus, in the system of regulation of the function of the thyroid gland, the central place occupies the thyrotrophs of the anterior lobe of the hypophysis, which secretes TSH. Remaining control over greater metabolic processes in thyroid parenchyma. This basic hospitality effect is made up to stimulation of production and secretion of thyroid hormones, and chronic - to hypertrophy and hyperplasia of thyroid gland.

On the surface of the thyrocyte membrane, there are specific alpha-subunits of the TSH receptor. The message of hormone interaction with them grows larger is standard for polypeptide hormones after reactions. The hormone-receptor complex activates adenylate cyclase, internal surface cell membrane. The block, which links the guanilic nucleotide, has a conjugating role in the interaction between the hormone-receptor complex and the enzyme. The factor, which is the origin of the stimulating infusion of the receptor on cyclase, can occur (3-sub-hormone. , the thyroid gland, stretching out the singing period, appears refractory to reintroductions hormone. Mechanism of the cAMP autoregulation reaction to TSH of nevidomas.

Approvals for TSH cAMP interchange in the cytosol with cAMP metabolism subunits of protein kinase, leading to catalytic subunits and activation of the cAMP cells until the end of the day. In the thyroid glands, the presence of phosphatase and phosphoproteins is attributable to a number of common types. The chronicity of TTG is to produce an increase in the amount of thyroid diet; because of the growth and the number of follicular clitins, which will increase the number of vitamins in a colossal space. In the culture of thyrocytes, TSH is characterized by the formation of microfollicular structures.

TSH is a great deal of reducing the iodine concentration of the thyroid gland, ymovirno, for the development of the mediated cAMP, the improvement of membrane penetration, supervascular depolarization of the membrane. However, the chronic action of TSH rapidly increases the concentration of iodide, on scho, mabut, bit by bit infusing the synthesis of carrier molecules. Great doses of iodide are not only by themselves involved in transport and organization of the rest, but also to reduce the reaction of cAMP to TSH, if you want and not to change the process of synthesis of the protein in the thyroid hall.

TSH stimulates the synthesis and iodization of thyroglobulin without any medication. From the beginning of the TTG quickly and rapidly growing with the growth of sour thyroid gland, it is, however, not related to the changes in the activity of oxidic enzymes, but to the increase in the availability of adenoic acid. TTG zbіlshu zalny rіvn of pyridine nucleotides in the tissue of the thyroid cavity, accelerating the cycle and synthesis of phospholipidіv in nіy, increasing the activity of phospholipase Ag, in order to start in the middle of the prostate

Thyroid hormone (thyroid hormone)

Thyroid hormone represented by two different classes of biologically active speeches: iodothyroninі polypeptide hormone calcitonin. The most important thing is that we are able to regulate the main exchange, and calcitonin is one of the officials in the growth and infusion of the calc exchange, as well as take part in the process of growth.

Microscopically, the tissue of the thyroid gland is represented mainly by spherical thyroid follicles synthesizing two so-called thyroid hormones - thyroxine (T4)і triiodothyronine (T3), Є iodinated by the obsolete amino acids to tyrosine and are reduced by the number of iodine atoms in the molecule, although they may have a special physiological power. Thyroid hormones are without a median involvement of TSH secretion by the adenohypophysis.

From 60 to 80 per cent of the extra thyroid hormone, which is violated by the thyroid gland, comes to the blood of the thyroxine, which is an apparently inactive thyroid hormone, in fact, it is a prohormone, which is weak by thyroid hormone. Before the time, as nadati diyu on the cells of organ-targets, a large portion of thyroxine in cells is converted into a biologically active form - triiodothyronin. The whole process is related to the role of metalloenzymes - selenium-fallow monodeiodinase.

In cells of the thyroid follicle epithelium there is a thyroglobulin protein. Tse of glucoproteins, to avenge the abundant excess of amino acid tyrosine (about 3% of the mass of the protein). Synthesis of thyroid hormones from tyrosine and iodine atoms in the storage of the thyroglobulin molecule, including 2 stages. On apical membranes, cytin follicles are combined with iodinated tyrosine from the formulations of monoiodothyrosine (MIT) and diiodothyrosine (DIT). The next step is the condensation of MIT and DIT with the statements T3 and T4.

Such an iodinated molecule is secreted by thyroglobulin into the lumen of the follicle, into the coloids. If a signal arrives at the thyroid gland from the TSH (thyroid stimulating hormone) vigil, the cells of the follicle consume the coloids at once with thyroglobulin, the enzymes of the protease lysosomes and hydrolyses the cells to amino acids, and when they are ready to go.

In the blood, thyroid hormones are linked to the carrier protein and in such a way they are transported in the tissue-targets. The concentration of T4 in the blood is 10 times more, lower than T3, so T4 is called the head form of thyroid hormones in the blood. Ale T3 is 10 times more active, lower than T4.

Tissue-targets for thyroid hormones - not all tissue, except for the spleen and family.

In tissue-targets, thyroid hormones are ringing from the bottle and coming to the cell. In cells, 90% T4 absorbs 1 iodine atom and transforms into T3. In such a rank, the head internal form of the hormone є T3.

The diet of thyroid hormones on the body is due to the concentration of hormones in the blood: in physiological doses, the stench is anabolic, in high doses - catabolic.

Physiological diya

Thyroid hormones stimulate growth and development of the body, growth and differentiation of tissues. To increase the demand for textiles in sourness. To increase the systemic arterial grip, the frequency and strength of the heart is very fast. Increase the temperature of the room and the level of the main exchange.

Thyroid hormones increase the level of glucose in the blood, increase gluconeogenesis in the liver, galvanize the synthesis of glucogen in liver and skeletal meat. The stench also stimulates the absorption and utilization of glucose by cells, increasing the activity of key enzymes in glucose. Thyroid hormones increase lipolysis (loss of fat) and reduce fat loss and release.

The diet of thyroid hormones for the exchange of bilks is based on the concentration of hormones. In the case of small concentrations of stinks, an anabolic effect on the exchange of bilks, stimulating the synthesis of bilks and galvanizing them, leads to a positive nitrogen balance. In the case of great concentrations of thyroid hormone, they reduce a strong catabolic effect on the blood exchange, increase the increase in blood flow and galvanization of synthesis, and as a heritage - a negative balance of nitrogen.

Thyroid hormones increase the sensitivity of tissues to catecholamines. The action of thyroid hormones on growth and development of the body is synergistic with the action of somatotropic hormone, and the manifestation of the singing concentration of thyroid hormones is a necessary brain for the manifestation of a number of effects of somatotropic hormone.

Thyroid hormones to enhance the processes of erythropoiesis in cystic brain... It is also injected into the water exchange, reducing the tissue dryness and tubular reabsorption of water.

Lecture 8.

Thyroid gland. Physiological effects of hormones in the thyroid gland.

1. Budova. Embryogenesis.

5. Mechanism of thyroid hormones.

1. Budova. Embryogenesis.

Shytovidny zloza є in all ridges. In humans, it is rosted in the anterior region of the shia, the trochus is lower than the cricoid cartilage of the larynx. It has three main parts: two small parts and a middle unpaired part - the isthmus.

In the process of human embryogenesis, the thyroid gland is laid on the 3rd intrauterine development. Already between the 12th and 14th levels of the internal uterine life, the thyroid gland is healthy to eat and accumulate iodine. Between the 15th and 19th tendencies, an organic connection to iodine and the synthesis of the hormone thyroxine should be repaired. Including, the thyroid zalosis has begun to function in the embryo back to its first generation, and hormonal activity is necessary for the development of the fetus.

The tissue of the thyroid gland is torn with semi-tissue prods on the edge of the patch. The main element of the її parenchyma є folikuli. The point of the skin follicle is composed of thyrocytes - one-globular cytoplasm, as two iodine hormones of the thyroid gland were violated. At a period of low functional activity, the eaters are flat, with an increase in them they become cubic and become cylindrical. In the middle of the follicle there is a coloid - the same mass secreted by the follicle by the epithelial follicle, which is to take revenge on iodine. The fluff is made from the follicles of the follicles, from the resulting fabrics, in which the purchase of epithelial cells - interfollicular islands, is used, as the basis for the adoption of new follicles.

At the stage of follicles and in the interfollicular islands, special cells of a round or oval shape are developed, which develop as light-colored cytoplasm ("light" cells). Increasing the activity of cych cells is caused by the perfusion of the thyroid gland with high calcium deposits. "Svitli" clitini take a part in the secretion of calcitonin, and that was called C-clitini or K-clitini (English - calcitonin abo Rus. Calcitonin). Deyaka a lot of "light" clitin in the process of evolution was playing in the last endocrine gorges - near-worm and thistle galls.

The thyroid gland loses itself in the body for a lot of blood circulation (through a gram of tissue for 1 xv of 5,6 ml of blood, through the nirki - only 1.5 ml), so to indicate the active endocrine function of the gullet. Innervatsiya zolozi be sympathetic, parasympathetic and somatic nerves. Bagato nice nerves end without a middle tie with follicles, but also for direct injection on the secretion of thyroid hormones.

2. Hormones of the thyroid gland and їkh affirmation.

Two iodine hormones (thyroxine and triiodothyronin) and three peptide hormones, which are included in the calcitonin family, are introduced to the thyroid hormones.

Thyroxine and triiodothyronin to establish themselves in the cells of the follicular epithelium. For the synthesis of cich hormones, it is necessary to continually go to the organism of inorganic iodine, which people will take away from iodide iodide and sodium iodide (in a good ratio - 100-200 mcg). In the body of people, 30-50 mg of iodine is taken, of which about 15 mg is in the thyroid zone.

Hormone formation in the thyroid zone pass the advancing phases:

1. Inorganic iodine, which needs to enter the body from the skin, get wet into the roof and come into the follicles of the thyroid gland, and concentrate. In the heat of iodides in the process of enzymatic oxidation, elementary iodine is generated.

2. Iodine is combined with the tyrosine molecule and becomes monoiodothyrosine and diiodotyrosine. When iodized tyrosine is oxidized, condenses and forms thyroxine and triiodotyrosine. The ratio of the synthesized thyroxine and triiodothyronine to become approximately 4: 1. The central role in the described processes is to form large-molecular glycoproteins. thyroglobulin , which includes surpluses of amino acid tyrosine and iodine. Thyroglobulin is synthesized by epithelial cells of follicles, and then accumulate in a coloid of follicular emptying. The very center of the molecule undergoes the processes of organic reaction to iodine, the release of iodine to tyrosine and condensation. In such a rank, the biosynthesis of thyroxine and triiodothyronine of substitution for uninterrupted production of thyroglobulin. Particularly, the process can be seen and without a middle in the thyrocytes.

3. Thyroid hormones are released from thyroglobulin and are seen in the blood. The process of repairing the colossal dots in the middle of the epithelial cells in the middle of the epithelial cells by way of pinocytosis, for which proteolytic cleavage of the thyroglobulin molecule Cathepsin by the lysosomes of the epithelial cells. The result is thyroxine, triiodotyrosine, as well as mono- and diiodothyrosine. Hormones penetrate into the roof of the blood, and iothyroidism is deiodinated.

The main thyroid hormone circulating in the blood is thyroxine. Thyroxine is located at the knitted with the stanzas. In humans, approximately 75% of circulating thyroxine is associated withα -globulin, 10-15% - with pre-albumin, small amounts - with albumin. Tsey zvyazyk maє werewolf character. Triioditonin can also be associated with blood plasmas, ale mensch, that is why the physiological action of it manifests itself more quickly, less thyroxine. Linkage with pereshkojaє blasts into the thyroid hormones through the nirks.

All the middle of the cells are penetrated only by vilny thyroxine and triiodothyronin, which are fixed by specific bottles. In peripheral tissues, the metabolism of thyroid hormones is observed, including deiodination. When thyroxine is common, it is often converted into biologically active triiodothyronine. in case of repeated deiodination, as well as the destruction of the peptide lance, the hormones will become more active.

The body of a grown-up human needs 100-300 mcg of thyroxine or 50-150 mcg of triiodothyronine. Thyroid hormone rampage to the end of the day: the period for thyroxine is close to 4 dB, and triiodirone is 45 years. Surplus hormones are ruined or transferred to the body. Metabolic degradation of hormones becomes the head rank in the oven. Moreover, vvazhayut, how metabolism is established may be physiological activity. Apparently, the product of thyroxine deamination strongly stimulates metamorphosis in amphibians (not vivified in patients).

The introduction of thyroxine and triiodothyronine from ooganism is transferred to glucuronic and hydrochloric acids in the liver. Confirmation of glucuronide and sulfoglucuronidum of thyroid hormones appear in the gum and from it into the intestine. A small part of cich conjugates is hydrolyzed by intestinal enzymes and reabsorbed into the roof. Deyaka number of thyroid hormones in vivodite nirkami.

3. Regulation of biosynthesis and secretion of thyroid hormones.

The main regulator of the function of thyroid follicles is thyrotropin ( hormone secreted by the anterior lobe of the hypophysis). Before injected thyrotropin, the following changes occur:

1. The growth of thyrocytes is observed (when the hypophysis is visible, the stench becomes flat, and when the thyrotropin is introduced - cubic or cylindrical);

2. Active biosynthesis of threoid hormones in winter stages:

Pidsilyu active transfer of iodides from the blood into the follicles of the clotting, setting the depolarization of cell membranes and increasing the ATP-ase activity;

Zbilshu oxidation of iodides, development of iodothyronin, synthesis of thyroglobulin;

pinocytosis of thyroglobulin and migration of thyroglobulin to lysosomes, splitting of the latter by proteolytic enzymes and the appearance of thyroxine and triiodothyronine in the blood is possible.

I will explain all the reasons why the ruining of the anterior lobe of the hypophysis is more difficult for atrophy of the parenchymal thyroid gland and hypothermia and why the excess production of thyrotropin can lead to the development of hyperthyroidism.

In connection with the hypophysis and thyroid gland, follow the principle of direct and vocal sound.

The secretion of thyrotropin is activated by thyreoliberin (thyrotropin-releasing factor), which is violated by neurosecretory elements of the hypothalamus. In such a rank, in organism, there is only one system: thyreoliberin-thyrotropin-thyroid hormone or the system of hypothalamus-hypophysis-thyroid gland. Signals from the central nervous system are transmitted through the hypothalamic region to the brain and the hypophysis to the thyroid gland, including those from the central nervous system. The whole mechanism lies in the basis of the state-of-the-art (1-2 dB) adjustment of the functional activity of the thyroid gland due to mental trauma in humans.

Between thyroid hormones and thyroid-stimulating hormones, from one side, and hypothalamic cells, when they are taking thyroid-thyroid hormones, - from the other side, as well as a heart attack: caused by the development of thyroid hormone disorders.

Vvazhayut, how cute nerves zbudzhuyut secretory activity of the thyroid gland, and parasympathetic - bring її. However, there is little direct evidence. Є Data about the contacts of sympathetic nerves with follicular cells. Vvazhayut, the autonomic nervous system is responsible for the nerves of the sudin (denervation of the thyroid gland does not overshoot the reaction to thyroid-stimulating hormone).

4. Methods for assessing the functional activity of the thyroid gland.

1. Assessment of the functional form of the thyroid gland for the size of the main exchange. The method of scoring on the tribute about those who iodine hormones create a basic exchange. However, the method is inaccurate, since the amount of the main exchange can be infused by the officials (the tone of the autonomic nervous system, the hormonal activity of the other endocrine worms, etc.).

2. Stagnation of radioactive iodine... Introduce a small dose of radioactive iodine (from 1 to 5 μCi) and after 2 to 24 years and then start clinging to iodine with thyroid gland (for example, for the aid of the Geiger-Muller hunter). With normal functioning of the thyroid gland, the accumulated iodine in it becomes: in 2 years - 7-12%, and in 24 years - 20-29% of the introduced amount. With a decrease in the function of the same value, the storage is generally 1-2 and 2-4%, and with an advanced function - 20-40 and 40-80%.

3. The number of plasmas tied with iodine bites (SBI). Have healthy people SBI to become 3.4-8 μg%, with thyrotoxicosis - at 8.5, and with hypothyroidism - less than 3 μg%.

4. The value of the reactivity of the thyroid gland to thyrotropin: A lot of the basal concentration of thyroid hormones in the plasma (syrovattsi) blood, and then the change in the introduction of thyrotropin.

5. Physiological meaning and mechanisms of thyroid hormone hormones.

Thyroxine and triiodothyronin may be even more wide-ranging for the function of the body.

Rist and development... A decrease in the secretion of thyroid hormones is reduced to a decrease in the main exchange by 40-50%. Shkira draws its elasticity, the hairy curl of the child, makes the robot heart. Children also have skeletal growth, development and maturity. Thyroxine and triiodothyronin are in conjunction with the growth hormone (somatotropic hormone). Vrodzhene underperformance or to see the visibility of the thyroid gland in humans cretinism ... Cretinism manifests itself in the deterioration of proportions of body, in the presence of growth, in the reduction of the main exchange, in the wrinkle of the curved fabrics, in the under-corrected mutilations, in the loss of pinkness, in the heartlessness, in the heart weakness, etc. The nature of the process of differentiation is damaged in embryogenesis, but it is still poorly understood. The reason for the development of spontaneous cretinism in humans may also be the chronic lack of iodides in the food races. Hyperfunction of the thyroid gland is necessary for anti-aging changes in the body of people.

Infusion on the nervous system... With the suppressed or abnormal functions of the thyroid gland on the cob stages of ontogeny, there is a glitch in the functions of the other symptoms of the brain: a decrease in the intellect-reflex action, a decrease in the reaction Hypotheriasis can lead to changes in the brain and peripheral nervous systems: the malaise of the nerve centers, peripheral ganglia and nerve-organ synapses decreases. Vvazayut, that in the basis of cycles of damage to lie there is a sharp decrease in the stages of differentiation of nerve tissue: change in the development of neurons, galvanization of development of nerve thermal, galvanization of synapse, reduction of nerve tissue On the idea of ​​some people, thyroxine is necessary to start the differentiation of nerve cells. Deficiency or excess of thyroid hormones in the critical period of development of the central nervous system is affected by changes in the development of the brain. The stench can be compensated for the normal balance of thyroid hormones only in the middle of the period, but not at all (for people in the first place, 3-6 months). After the completion of the critical period of development of the winery, the snakes in the nerve cells become non-gated.