The Effect of Central Insulin on Insulin Sensitivity and Energy Metabolism

Insulin has a direct effect on the energy metabolism of the brain under basal conditions and has an effect on the hepatic glucose production, lipid metabolism and the secretion of various hormone. The effect of intranasal insulin on peripheral metabolism in humans supposedly is mediated by the vagus nerve. The purpose of this study is to determine whether central insulin influences the human peripheral insulin sensitivity of liver and muscle and whether vagus nerve stimulation can mimick this effect.