Hormones of the pancreas are of biological importance.

Functions of the pancreas. The incremental function of the pancreas is due to the specialized cells of the islets of Langerhans - α-, β-, D- and F-types. The cells of each of these types secrete certain hormones: the Langerhans island β cells synthesize insulin, α cells-glucagon, D-cells-somatostatin, pancreatogastrin and secretin, the F cells synthesize hormone-like substances (lipocaine and vapo- toin). Therefore, the pancreas is an important organ that takes part in the regulation of metabolic processes. Hormones, synthesized by this gland, affect all kinds of metabolism in the body. Insulin was discovered by L.V. Sobol'ev as early as 1902. In the middle of the 19th century, the structure of the hormone was established and its synthesis was performed.

Hormones of the pancreas: insulin. The targets of free insulin are liver cells, muscle and connective tissues. Insulin affects all types of metabolism: protein, carbohydrate, lipid, but its effect on the metabolism of carbohydrates is best studied. First of all, insulin enhances the permeability of cell membranes to glucose and this ensures its transition from blood to tissue. This hormone activates the enzyme phosphoglucotransferase (hexosokinase) and thus ensures the conversion of glucose into glucose-6-phosphate. The end result of the effect of insulin on the metabolism of carbohydrates is a decrease in the concentration of glucose in the blood (hypoglycemia) and the accumulation of glycogen in the muscles, liver and other organs. Due to insulin deficiency, cells lose the ability to use glucose. Its amount in the blood gradually increases (hyperglycemia), and it begins to be excreted in the urine (glycosuria).

In addition to glucose, insulin promotes more active transport of amino acids from blood, lymph to the cytoplasm of cells, activates transcription and translation, thereby increasing protein synthesis.

The effect of insulin on lipid metabolism is due to the fact that it provides the use of carbohydrates for the synthesis of higher carboxylic acids, and already from them triacylglycerols and other lipids are formed. On the other hand, insulin inhibits tissue lipase, including by inhibiting the formation of cAMP. Insufficient formation of insulin in the body is accompanied by an increased disintegration of amino acids, which ultimately leads to the accumulation of ammonia and urea in the blood. Activates lipolysis, which leads to the accumulation in the blood of free fatty acids, ketone bodies and cholesterol.

Hormones of the pancreas: glucagon. Glucagon targets are liver, adipose tissue and muscle cells, but the main one is the liver, in which phosphorylase activates under the influence of glucagon, which in turn activates the hydrolysis of glycogen. Therefore, the amount of glycogen in the liver decreases, and the glucose in the blood increases. In addition, glucagon enhances gluconeogenesis, activates lipolysis of adipose tissue and thereby prevents the development of obesity. This is accompanied by the formation of a large number of acetyl-CoA and ketone bodies. Glucagon secretion decreases with hyperglycemia, but increases with stress and hard work.

Hormones of the pancreas: somatostatin. This hormone inhibits the growth of insulin and glucagon, the secretion of gastrin and gastrin-stimulating secretion of hydrochloric acid. Violations of the increment of insulin, glucagon, as well as somatostatin are at the heart of the development of diabetes mellitus. This disease is characterized by general weakness, hyperglycemia, glucosuria, polyuria (daily urine quantity is increased 3-5 times), diabetic cataract occurs, and corneal opacity is recorded.

Hormones of the pancreas: lipokain and vagotonin. Lipocaine is a hormone-like substance that prevents fatty liver, it stimulates the oxidation of fats, fatty acids and their release from the liver into tissues, promotes the biosynthesis of phospholipids. Vagotonin stimulates the activity of the parasympathetic nervous system, primarily the vagus, activates the processes of hematopoiesis.