Hormones

GETROPIN

Somatotropin (Growth hormone) is polypeptide hormone secreted by adenohypophysis. It contains 191 amino acids and has a molecular weight of 22 kDa. The production and release of human growth hormone is regulated by hypothalamic somatotropin-releasing factor (GRF) and somatostatin. Time and frequency of release are regulated by somatostatin, the amount of released hormones is regulated by GRF.

Somatotropin is anabolic hormone, that stimulates processes of mitosis. Somatotropin increases the release of free fatty acids from adipose tissue, accelerates the transport of glucose and promotes the accumulation of glycogen.

The hormone also accelerates the growth of bones and soft tissues due to acting through the insulin growth factors. It accelerates the synthesis of protein, providing a positive nitrogen and phosphorus balance and reducing the level of urea. Due to high demand of growing tissues in ions, GH inhibits excretion of sodium and potassium, increases calcium absorption in the intestine, stimulates lipolysis in adipose tissue, mobilizes fatty acids and activates their absorption from the muscles and liver (where they are converted into glucose). Somatotropin increases glucose blood levels by preventing its absorption by tissues, acts on the immune system increasing the number of

T-lymphocytes, enhances body perspiration. Food intake decreases the secretion of GH and during hunger the secretion of GH is increased by 15 times.

The production of hormone is increased during physical activity, sleep, in hypoglycemia. Excessive production of somatotropin leads to gigantism, in adults acromegaly. Decreased production during growth period leads to dwarfism. In adults visible symptoms of low hormone secretion are not observed.