Abstract

Glucagon is a polypeptide secreted by the α -cells of the pancreatic islets; it consists of 29 aminoacids arranged in a single chain. Its most important physiological effect is probably the stimulation of glucose output from the liver, but at concentrations higher than those found physiologically, glucagon increases the contractility of heart muscle as do the catecholamines. This inotropic effect of glucagon may therefore find a new role in therapeutics.