Fear-cue Induced Inhibition of Feeding

Abstract

Previously our lab has shown that food-deprived male and female rats will inhibit food consumption when presented with a conditioned stimulus that signals danger, and that this effect persists much longer in females than in males. The current experiment is part of a larger study that has two aims: 1) delineate the brain areas associated with fear-cue induced anorexia and 2) determine whether there are sex-differences in brain activation patterns. Female rats previously conditioned in an aversive paradigm inhibited food intake compared to female rats in the control group during three extinction tests, while experimental males only inhibited intake compared to male controls during test one. Following the third test, rats were sacrificed and brain tissue processed to assess activation patterns via Fos-expression within the central nucleus of the amygdala (CEA). We found that males had higher activation than females during test 3 in the CEA.