Insulin (from the Latin insula – island) – a hormone of peptide nature, is formed in beta cells of the islets of Langerhans pancreas. Has a multifaceted influence on the exchange in almost all tissues. The main effect of insulin is to reduce the concentration of glucose in the blood. In bodybuilding, insulin is used because of its pronounced anabolic effect. An alternative is oral hypoglycemic agents, such as Diabeton. 1ml insulin syringe
Insulin increases the permeability of plasma membranes for glucose, activates key glycolysis enzymes, stimulates the formation of glycogen in the liver and muscles, and enhances the synthesis of fats and proteins. In addition, insulin inhibits the activity of enzymes that break down glycogen and fats. That is, in addition to anabolic action, insulin also has an anti-catabolic effect.
Most of the insulin depends on the transport of glucose in two types of tissues: muscle tissue and fatty tissue is the so-called. Insulin-dependent tissues.
Effects of insulin
Metabolic effects of insulin
- Increased absorption of glucose and other substances by cells;
- Activation of key glycolysis enzymes;
- An increase in the intensity of glycogen synthesis – insulin boosts the storage of glucose by the cells of the liver and muscles by polymerizing it into glycogen;
- A decrease in the intensity of gluconeogenesis – the formation of glucose in the liver from various substances of non-carbohydrate nature (proteins and fats) is reduced.
Anabolic action of insulin
- Enhances the absorption by cells of amino acids (especially leucine and valine);
- Enhances transport to the cell of potassium ions, as well as magnesium and phosphate;
- Enhances DNA replication and protein biosynthesis;
- Enhances the synthesis of fatty acids and their subsequent esterification – in adipose tissue and in the liver, insulin promotes the conversion of glucose into triglycerides; With insulin deficiency, the opposite happens – the mobilization of fats.
Anticatabolic action of insulin
- Suppresses hydrolysis of proteins – reduces protein degradation;
- Reduces lipolysis – reduces the flow of fatty acids into the blood.