The role of the gastric and hepatic vagus in voluntary alcohol intake.

The present study investigated a possible role for neural signals sent from the liver and stomach to the brain in the regulation of alcohol intake. Experiment 1 showed that gastric vagotomy (GVX) reduced the intake of 3% alcohol and 6% alcohol, while water intake was increased. This effect was not due to an alteration in pharmacokinetics, although an alteration in taste function could not be ruled out. Angiotensin II reduced the intake of 6% alcohol and stimulated the intake of water similarly in both GVX and sham groups. In Experiment 2 rats were subjected to hepatic vagotomy or sham laparotomy and then offered a choice between an alcohol solution and tap water for 40 min each day. Although hepatic vagotomy (HVX) did not alter the intake of 3% alcohol or water, 6% alcohol intake was significantly reduced. Angiotensin II decreased 6% alcohol intake and increased water intake similarly in both groups. These experiments indicated that interrupting information from the liver and stomach to the brain by selective gastric and hepatic vagotomy can decrease voluntary alcohol intake. Since vagal afferent nerves are thought to participate in the control of food intake, the present findings support the hypothesis that the "food-like" qualities of alcohol, i.e., calories and taste, can contribute to the regulation of alcohol intake.