Neural Control of Islet Function by Norepinephrine and Sympathetic Neuropeptides

Abstract
Stress activates the sympathoadrenal system increasing the circulating levels of epinephrine (EPI) and norepinephrine (NE). Both the magnitude of the plasma catecholamine response and the resultant hyperglycemia are dependent on the severity and type of stress. Severe stress also alters the secretion of the metabolically-active hormones, insulin (impaired relative to the hyperglycemia) and glucagon (enhanced despite the hyperglycemia). Most evidence links the activation of the sympathoadrenal system to these changes of pancreatic hormone secretion, suggesting that either the increase of adrenomedullary EPI or increased activity of the sympathetic nerves of the pancreas mediates these changes of insulin and glucagon secretion.