Effects of intra-amygdalar dopamine agonists and antagonists on gastric stress lesions in rats.

Microinjections of dopamine (DA, 3 and 30 micrograms) or its agonist apomorphine (3 micrograms) into the central amygdala (CEA) attenuated cold restraint (3 h at 4 degrees C)-induced gastric ulcer formation in rats. Pretreatment with DA antagonists, haloperidol and metoclopramide (both i.p. and intra-amygdalar) reversed the stress ulcer attenuating effect of DA. It is suggested that the CEA is one of the central sites for this DA cytoprotection and that D2 receptors are possibly involved in this effect.