CH 37 Regulation of blood glucose

arne1's version from 2015-09-26 16:09


Question Answer
Fasted state in pancreashigh blood glucose stimulates beta cells of pancreas to secrete insulin. At the same time alpha cells of the pancreas are inhibited, leading to lower glucagon levels.
insulin receptors on cell membrane tyrosine kinase receptors
Glycogen synthase is active in the dephosphorylated form
Action of insulininsulin dephosphorylates key enzymes
Role of glucokinaseto provide G6P for the synthesis of glycogen. it stimulates glycogenensis by activating glycogen synthase (dephosphorylated).
Glucose entry NOT dependent on insulinentry into neurons (GLUT-1, GLUT-3) and RBCs (GLUT-1)
Low glucose effect on pancreasbeta cells inhibited (insulin) and alpha cells stimulated (glucagon). Key enzymes are phosphorylated.
Gluconeogenesis becomes active due todecreased fru 2,6 bisphosphate in liver (it is increased by insulin and stimulates glycolysis)
Key enzymes of gluconeogenesisPEPCK, pyruvate carboxylase, fructose 1,6 bisphosphatase, glucose 6 phosphatase.