Elevation of Plasma Epinephrine Levels Produced by Glucagonin Vivo

A single injection of glucagon (50 μg/kg) given to anesthetized dogs rapidly elevates glucose, lactate and epinephrine levels in peripheral plasma. A 10-min infusion of glucagon (0.1 mg/min) produced a marked elevation of both epinephrine and norepinephrine in adrenal vein blood. These data are in accord with the conclusion that the hyperglycemic response to glucagon is the resultant of the combined effects of rapid hepatic glycogenolysis and stimulation of the release of epinephrine, which acts to depress the rate of glucose uptake by peripheral tissues. Evidence for the postulate that hypoglycemia stimulates release of glucagon, which in turn elicits the release of epinephrine, is discussed.