 Keywords: a pituitary body, an adenohypophysis, Hormonum, a hypothalamus, hypothalamo-hypophysis system, Adrenocorticotrophinum, Somatotropinum, tireototropic hormone, Prolactinum, somatotropic hormone, Hormonum of body height, a nanism, a gigantismthe Author: Poljanskaja O.V.PHYSIOLOGY OF THE ADENOHYPOPHYSISAdrenocorticotrophinumis a cleavage product large (239 AK) glikoproteina propiomelanokortina, formed bazofilnymi kortikotrofami. This fiber shares on two parts, one of which at splitting is a source of Adrenocorticotrophinum and melanokortina, and the second, termed lipotropinom, - being split, gives except for melanotropina morfinopodobnyj the peptide endorphins playing the major role in antinotsitseptivnoj (antipain) system of a brain and in modulation of a secretion of Hormonums of an adenohypophysis. The secretion of Adrenocorticotrophinum occurs constantly pulsating flashes to precise daily rhythm. The best concentration of Hormonum in a blood is marked in the morning, and most from 22 o'clock till 2 o'clock. The regulation of a secretion is submitted by straight lines and feedback. Production of Adrenocorticotrophinum sharply grows at action by an organism of strong irritants, for example, colds, pains, an exercise stress, emotions, and also under influence of a hypoglycemia. Effects:
Gonadotropinums.the Secretion has well defined cyclicity both at men, and at women. Molecules sekrktirujutsja with attached on the end of carbohydrate chains of a glycoprotein sialine acids that protects them from destruction in a liver. The main brake effect on production follitpropina renders on mechanism OOS Hormonum of spermaries ingibin. Hormonum of an adenohypophysis Prolactinum brakes a secretion of Gonadotropinums; allocation ljutropina oppress and gljukokrtikoidy. Effects: follitropin causes body height of follicles of an ovary and a proliferation of cells granulyozy in women, body height of testicles, a proliferation of cells Sertoli and a spermatogenesis at men. Ljutropin causes an ovulation and body height of a yellow body in ovaries, stimulates cells Lejdiga in spermaries. the Thyrotropinis secretioed continuously, with precise fluctuations within day, thus the maximum of the maintenance in a blood falls at the hours previous to dream. Glucocorticoids brake a secretion. The thyrotropin is secretioed in the increased amounts at action on an organism of low temperature, other influences - a trauma, a pain, a narcosis - secretion of Hormonum suppress. The thyrotropin is bound to a specific receptor of follicular cells of a thyroid gland and causes metabolic reactions with the help of 4 secondary intermediaries: tsAMF, инозитол-3-фосфата, DAG and complex Sa + kalmodulin. The thyrotropin enlarges a secretion of Hormonums of a thyroid gland activation of a hydrolysis of a thyreoglobulin. Due to augmentation of synthesis of a RNA and fiber the thyrotropin causes augmentation of mass of a thyroid gland. Vnetireoidnoe action of a thyrotropin is shown by rising of formation glikozaminoglikanov in a skin, hypodermic and zaorbitalnoj to a fat. It usually happens because of realization of a feedback at insufficient production of a thyroid gland, for example, at deficiency of Iodum. The supersecretion of a thyrotropin results in occurrence of a struma, giperfenktsii a thyroid gland with effects of excess of thyroid Hormonums (thyrotoxicosis), pucheglaziju (ekzoftalm), that in aggregate name " Bazedova illness ". Somatotropinumis secretioed continuously and "flashes" in 20-30 minutes with a distinct daily rhythmicity. Rising a secretion of Somatotropinum occurs during deep dream, at his early stages (popular wisdom says: " the person grows, when sleeps "), after muscular loads, under influence of infections and traumas. Stimulate production of Somatotropinum Vasopressinum and endorphins, and also changes of a metabolism. So, the hypoglycemia activates a secretion somatoliberina and Somatotropinum, and the hyperglycemia - brakes; excess AK and downstroke of free fat acids in a blood activate a secretion. Effects: are connected to influences on a metabolism, the majority from which it is realized by special humoral factors (Hormonums) of a liver and the osteal tissue, received the name somatomediny. As effects somatomedinov on a metabolism in many respects are similar to effects of an insulin, they are named quite often still with insulinoid factors of body height. These effects are shown. In particular, in simplification of recycling of a glucose tissues, activization in them of synthesis of fiber and Adeps. Somatomediny realize effects of Somatotropinum due to specific influences on hrjashchevuju a tissue: stimulations of inclusion of Zinci sulfas in synthesized proteoglikany, stimulations of inclusion of a thymidine in formed by a DNA, activation of synthesis of a RNA and fiber. At the same time the differentiation prehondrotsitov, rising of transport AK through their cellular membrane is provided not somatomedinami, and Somatotropinum. Though somatomediny also name insulinoid factors of body height, receptors of a cellular membrane for them differ from receptors of an insulin. The described effects are characteristic for short-term action of Somatotropinum or an early phase of his influence. At a long and excessive secretion of Somatotropinum effects get kontrinsuljarnye features. The combination of a stimulation of a secretion of an insulin to his destruction and suppression of effect is observed. It can result in a diabetes which by origin name pituitary. Hormonum renders permisivnoe (facilitating) action in relation to effects of catecholamins and gljukokrtikoidov, consequence of that is the stimulation of a lipolysis of a fatty tissue, rising of a level of free fat acids in bloods, superfluous formation ketonovyh bodies in a liver (ketogennyj effect) and even fatty infiltratsija a liver. Insulinrezistentnost taknej can be connected and to these shifts of a fatty exchange. Augmentation of the sizes of internal organs - a splanchnomegaly. Prolactinum.Synthesis and a secretion are adjusted subthalamic by a neuropeptid - inhibitor prolaktostatinom and a stimulator prolaktoliberinom. Formation of these subthalamic peptides occurs in dofaminergicheskih neurones of a hypothalamus. The secretion depends on a level in a blood of oestrogens, glucocorticoids and thyroid Hormonums. In dairy Ferri lactases Prolactinum vlijant on processes of formation of milk, instead of on his allocation. At that Hormonum stimulates synthesis of fiber - laktalbumina, and also Adepses and carbohydrates of milk. For a regulation of body height and development of dairy Ferri lactases by synergists of Prolactinum oestrogens are, but at the begun lactemia oestrogens - antagonists of Prolactinum. The secretion of Prolactinum is stimulated reflexly by the act of a suction. Effects: promotes maintenance of secretory activity of a yellow body in ovaries and to formation of Progesteronum. Prolactinum is one of regulators of a water-salt exchange of an organism, reducing an egestion of water and electrolits, strengthens effects of Aldosteronum and Vasopressinum, stimulates body height of internal organs, an erythrogenesis, promotes occurrence of an instinct of a maternity. Besides intensifying synthesis of fiber, Prolactinum raises formation of Adeps from carbohydrates, promoting a postnatal obesity. Hromofobnye cells according to the present classification refer to as zero cells. These cells are a source for formation of nonfunctioning adenomas of a pituitary body. Some researchers consider, that zero cells do not accept participation in gormonoobrazovanii, and are only a source from which other types of cells of a forward share of a pituitary body are differentiated. It is not excluded also, that zero cells secretio for the present not identified Hormonums, such, as adrenal androgenstimulirujushchy Hormonum, jaichnikovyj the factor of body height, aldosteronstimulirujushchy Hormonum. Under some conditions in a pituitary body it is taped horionichesky Gonadotropinum, but the source of his formation is not fixed yet. As have shown researches To Saccomanno and soavt. (1944), nonfunctional adenomas of a pituitary body secretio horionichesky Gonadotropinum which insignificant amounts are found out in Serum of a blood and in healthy men. E. Horvath and K.Kovacs (1995), having applied histological and other kinds of researches at studying 1700 adenomas of a pituitary body, have offered the modified classification in view of frequency of occurrence of various kinds of adenomas:
THE HYPOPITUITARISM.The infrequent disease connected to downstroke or complete deenergizing of function of a forward share of a pituitary body. Failure of all Hormonums of an adenohypophysis causes a deep attrition with decrease of mass of all tissues, especially muscular and a fatty - pituitary cachexia. The basic exchange is reduced more sharply (almost in 2 times), than at complete thyroid failure. The blood pressure and a body temperature are reduced a level of a glucose in a blood is lowered, kompensatorno sensitivity of tissues to an insulin (thyroid Hormonums and corticosteroids) grows. Sexual function stops, and initial sexual attributes will atrophy (Gonadotropinums, sexual corticosteroids), are blasted and a teeth (Somatotropinum, thyroid), a skin atrofichnaja, dry drop out and rugosity, hair drop out (thyroid). More sharply, than at thyroid failure, the status - flaccidity, an adynamia, apathy, infringements of intelligence is broken mental, patients remind very old men. Usually carry out replaceable therapy by combinations of several Hormonums of an adenohypophysis, carefully monitoring at the patient a glycemia and a level of the basic exchange. The initial hypopituitarism is connected to absence of cells of an adenohypophysis, again - with failure of a secretion of Hormonums. Isolated failure - is not present only one Hormonum (more often - Gonadotropinum, somatotropic hormone). The hypopituitarism is shown, when normally function less than 30 % of cells of an adenohypophysis. A hypopituitarism can cause:
Isolated failure of Somatotropinum can be a different degree of an expressiveness and arises at any stage of an ontogenesis. It is described and hereditary failure of Somatotropinum. Besides organic damages of an adenohypophysis, deficiency of Somatotropinum can be caused by rising of a level of fat acids in a blood, an obesity, superfluous effects of Progesteronum, gljukokrtieoidov, stimulators of v-adrenoreceptors, antagonists of a serotonin, Dofaminum, infringements of function of a thyroid gland. At a nanism development of a brain, mental and intellectual development do not suffer due to adequate function of a thyroid gland and compensator reactions of other Hormonums of body height. General law of indemnification of deficiency of Somatotropinum: the later in an ontogenesis deficiency of Somatotropinum is shaped, the more easy he is compensated. Indemnification is carried out due to fabric influences of Adrenocorticotrophinum and thyroid Hormonums, and also insulinoid factors of body height. The last are formed and secretioed by many tissues (to cookies, hrjashchevoj a tissue, an epithelium, etc.) under influence of Somatotropinum, however, these growth factors and neogeneses, no less than series of others tsitokinov cellular mitogenov, can be activated and at deficiency of Somatotropinum under influence of other Hormonums. To discuss a material at a forum of a site Keywords: a pituitary body, an adenohypophysis, Hormonum, a hypothalamus, hypothalamo-hypophysis system, Adrenocorticotrophinum, Somatotropinum, tireototropic hormone, Prolactinum, somatotropic hormone, Hormonum of body height, a nanism, a gigantism Main | Abstracts, compositions, lectures | Psychiatry | Links
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