A schematic representation of the autoregulatory control of the size of the blood glucose pool.
Glucose homeostasis is presented as a self-regulating plumbing system. Blood glucose concentration rises as glucose enters the blood from the intestine. This in tum activates insulin secretion by direct action on the pancreas, and also through higher centres. Consequently, glucose inflow from the liver (from glycogen) is reduced, and outflow into the tissues is increased. During fasting, glucose inflow from the gut ceases; blood glucose concentration reaches basal levels; insulin secretion and outflow of glucose into the tissues almost cease; and glucose release from the liver (glycogen) is activated so that inflow exactly balances outflow into the brain and erythron. The ΓÇÿinsulin-sensitive valveΓÇÖ can be activated by both endogenous and exogenous insulin.
