The effect of naloxone in different gastroduodenal ulcer models.

On the basis of our investigations it seems that: The opiate antagonist naloxone in a dose of 5.0 mg/kg has a significant protective effect in stress-ulcer model in the rat; No such effect was seen in drug (indomethacin) or cysteamine induced (duodenal) ulcer models; The interaction of naloxone with indomethacin seems to show a sex-difference.