Электронная библиотека технического вуза
Main subjects:
10.1. Role of hormones in regulation of metabolism
10.2. Regulation of carbohydrate, lipid, and amino acid metabolism
10.3. Regulation of metabolism of the main energy substrates
10.4. Diabetes mellitus
10.5. Regulation of water and salt metabolism
10.6. Disturbances of water and salt metabolism
10.7. Regulation of calcium and phosphate metabolism
10.8. Hypoand hypercalcemia
10.1. ROLE OF HORMONES
IN REGULATION OF METABOLISM
The consistency of body homeostasis is provided by regulatory systems:
• Central and peripheral nervous system - due to signal transduction by means of nerve impulses and neurotransmitters.
• Endocrine system - with the help of hormones which are synthesized by specialized cells and transported by blood to target-tissues.
• Paracrine and autocrine systems - with participation of signal molecules secreted from cells into extracellular space and affecting the same or neighboring cells. Eicosanoids, hista-mine, gastro-intestinal hormones and cytok-ines function in this way. Cytokines (interleu-kins, factors of growth and cell differentiation, interferons) are low-molecular glycoproteins, which play the role of transmitters in inflammatory processes, mechanical injuries, and virus infections.
• Immune system - by means of specific proteins: antibodies, T-receptors, proteins of the major his-tocompatibility complex.
All regulatory levels function in the body as an integrated system.
INTERPLAY OF THE NERVOUS AND ENDOCRINE REGULATORY SYSTEMS
Central nervous system receives signals from external and internal environment. By neurons of nervous
cells these signals enter hypothalamus where protein releasing factors are synthesized: liberins and statins. They regulate the synthesis and secretion of anterior pituitary gland hormones (tropic hormones), while liberins stimulate and statins inhibit these processes. Tropic hormones are glycoproteins. They are secreted into blood and transported to endocrine glands stimulating the synthesis of appropriate hormones by peripheral endocrine glands. Peripheral gland hormones enter the bloodstream and interact with receptor-proteins of target-cells and influence the metabolism changing the rate of compound transport into cells, activity or quantity of specific proteins and enzymes