Does selective vagotomy affect conditioned flavor-nutrient preferences in rats?

We investigated the effects of selective vagotomy on the learning of conditioned flavor preferences associated with intragastric Polycose infusion. Normal control, hepatic branch vagotomized, and gastric vagotomized rats implanted with gastric catheters received a flavor (CS+) paired with intragastric Polycose infusion, and on alternate days, a different flavor (CS-) paired with intragastric water infusion. After training, rats were given a two-bottle extinction test for 12 days. The results show that normal control and hepatic branch vagotomized rats had a significant CS+ flavor preference during extinction testing, whereas the gastric vagotomized rats showed no preference. This result indicates that the hepatic branch of the vagus does not play a solitary role in learned flavor-nutrient preferences using Polycose. However, the gastric vagal branches may be involved in the preference learning.