Effects of hepatic denervation on the anorexic response to epinephrine, amphetamine, and lithium chloride: a behavioral identification of glucostatic afferents.

Intraperitoneal injections of epinephrine (20, 40, 80, and 160 microgram/kg) and amphetamine (.1, .2, and .4 mg/kg) were administered to rats with various forms of hepatic denervation. In Experiment 1, destruction of the esophageal trunks of the vagus attenuated epinephrine and amphetamine anorexia, but destruction of the hepatic vagus did not. In Experiment 2, rats with celiac ganglionectomy, subdiaphragmatic vagotomy, or the combined operation all exhibited decreased epinephrine anorexia to the same extent. However, ganglionectomized rats were less responsive to amphetamine anorexia than were vagotomized ones. Vagotomized rats were significantly more reactive to lithium chloride (10, 20, and 30 mg/kg) than were controls. These results suggest that the major component of hepatic metabolic afferent fibers travels from the liver, through the celiac ganglion, and into the esophageal vagal trunks where they ascend to the brain. The anorexic action of amphetamine appears to result from a centrally induced sympathetic action on the liver.