Deeper understanding of - insulin receptor

Author: zho

The level of insulin in the cell biological role of the target cell membrane through specific receptor binding and activated. The role of insulin receptor for insulin target specific parts of the cell membrane, only containing insulin and insulin or proinsulin molecules with a high degree of specificity, and a very wide distribution. Receptor is a glycoprotein, each receptor by α, β-subunit composition of the two. α-subunit through the cell membrane, one end exposed to the membrane surface, with the insulin binding site. β subunit of the membrane to the cytoplasm by an extension of the insulin-induced membrane and cellular effects of functional units. Combination of insulin and after subunit, β subunit of tyrosine kinase is activated, so that receptor phosphorylation, resulting in mediator to regulate the activity of intracellular enzyme systems, control metabolism.

Each combination of cells and depends on insulin receptor number and affinity, the two also by adjusting the concentration of plasma insulin. When insulin concentrations are often increased the number of insulin receptors decreased, Down-regulation said. Such as the obese non-insulin-dependent diabetes mellitus because of the number of fat cell membrane receptor decrease was clinically non-insulin sensitivity, said resistance. When the obese non-insulin-dependent diabetes by diet control, weight loss after physical exercise, the fat cell membrane insulin receptor number increased, and insulin-binding capacity strengthening to improve the use of blood glucose. This is not only the obese non-insulin-dependent diabetes mellitus pathogenesis of an important, but also the treatment of the theory must be based on weight loss.