Selective hepatic vagotomy blocks pancreatic glucagon's satiety effect.

To test the hypothesis that hepatic vagal afferents mediate the satiety effect of pancreatic glucagon, we tested the effects of selective surgical and pharmacological lesions of the abdominal vagus on glucagon's potency to inhibit feeding. Surgical disconnection of only the hepatic branch of the abdominal vagus blocked glucagon's satiety effect as well as total abdominal vagotomy. However, abdominal vagotomy that spared the hepatic branch did not change glucagon's satiety effect. Glucagon also inhibited feeding after pharmacological blockade of peripheral postganglionic muscarinic receptors with atropine methylnitrate. All these results are consistent with the hypothesis that hepatic vagal afferents mediate the satiety effect of pancreatic glucagon.