Interactions amongst factors which influence severity of gastric ulceration in rats.
A number of factors have previously been demonstrated to influence the severity of stress-induced gastric ulceration in rats, including prior exposure to pre-shock and allowing animals a post-stress rest or recovery period. The primary purpose of this experiment was to investigate how one of these factors might modulate the expression of the other. Animals were pre-exposed to either signalled or unsignalled shock (using "learned helplessness" parameters), or no shock. They were later subjected to 2 hours restraint-in-water (immersion) stress, or appropriate handling control procedures. Half of the animals were sacrificed immediately on removal from the water-restraint, and half were sacrificed after a 2 hour recovery period in their home cages. Analysis of the severity and number of glandular stomach lesions indicated that animals subjected to the pre-shock exhibited greater ulceration than unshocked animals, as long as no post-stress rest period was allowed. Additionally, the effect of post-stress rest was masked by experience with pre-shock. This reciprocal modulation of treatment influences may offer suggestions for understanding discrepancies in the literature on the effects of these two modulating variables.
D000818:Animals; D003345:Corticosterone / Q000097:blood; D004195:Disease Models, Animal; D004597:Electroshock; D006234:Handling, Psychological; D006380:Helplessness, Learned / Q000523:psychology; D007101:Immersion; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012149:Restraint, Physical; D013016:Sound; D013276:Stomach Ulcer / Q000209:etiology*; D013312:Stress, Physiological / Q000150:complications*
D003345:Corticosterone