PREVENTION OF STRESS-INDUCED GASTRIC-ULCERS BY MU-OPIOID AND DELTA-OPIOID AGONISTS IN THE RAT

The effects of intraperitoneal and intracerebroventricular administrat ion of mu- and delta- selective opioid receptor agonists (DAGO and DPD PE, respectively) on gastric lesions. were investigated in cold-restra int-stressed rats. DAGO and DPDPE, peripherally and centrally administ ered. induced a significant gastric protection. Naloxone prevented the effects of both opioids whereas naltrindole prevented the gastric pro tection induced by DPDPE but not that by DAGO. The results suggest tha t mu- and delta-opioid agonists prevent gastric damage induced by stre ss through an involvement of both central and peripheral mu- and delta -opioid receptor subtypes.