ABSTRACT
The major hormonal regulators of glucose homeostasis are glucagon and insulin. Defects in the mechanism controlling glucose homeostasis are relatively common in humans, the most widespread of these being diabetes. The endocrine pancreas is made up of four major cell types and the regulated secretion of peptide hormones from these cells provides the main mechanism by which the body achieves glucose homeostasis. The effects of insulin on glucose homeostasis are largely mediated through a reduction in hepatic glucose output with simultaneous stimulation of glucose uptake into muscle and adipose tissue. The importance of hepatic glycogenolysis and glucose-6-phosphatase in regulating whole body glucose homeostasis is illustrated by the pathophysiology of type-1 glycogen storage disease. The close links between obesity and insulin resistance suggest that events occurring in adipose tissue may influence whole body glucose homeostasis. The insulin receptor has a crucial role in glucose homeostasis and decreasing levels of insulin receptor function are inversely related to the degree of insulin resistance.
