Effects of amygdaloid lesions on gastric erosion formation during exposure to activity-stress.

To examine the role of the amygdala in the production of gastric ulcers induced by activity-stress, electrolytic lesions were placed in the centromedial (CENT) and medial (MED) amygdaloid nuclei, as well as in the intra-amygdaloid division of the bed nucleus of the stria terminalis (BNST). As compared to sham-operated controls (CONT), gastric ulceration was attenuated in rats with CENT lesions and exacerbated in rats with lesions located in the BNST or MED. Wheel running did not differ significantly between control animals and lesioned rats, but did differ within lesioned groups. Rats with MED lesions ran more than rats with CENT or BNST lesions. Results support the view that the integrity of the centromedial amygdala is critical for the maintenance of the viscera and demonstrate that neurogenic factors contribute to the development of gastric erosions during exposure to activity-stress.