THE EFFECT OF MISOPROSTOL ON ASPIRIN-INDUCED GASTRODUODENAL LESIONS IN DOGS

Misoprostol, a synthetic prostaglandin E(1) analog, is effective in tr eating and preventing nonsteroidal antiinflammatory drug (NSAID)-induc ed gastrointestinal lesions in humans. The effectiveness of misoprosto l in preventing aspirin-induced gastroduodenal injury was studied in 3 groups of 6 adult mixed breed dogs. Group I received 3 mu g/ kg misop rostol PO tid. Group II received 3 mu g/kg misoprostol PO tid and 35 m g/kg aspirin PO tid. Group III received 35 mg/kg aspirin PO tid. Endos copy was performed on days 0, 5, 14, and 30. Five regions of the upper gastrointestinal tract were qualitatively scored from 1 to 12 based o n the presence of submucosal hemorrhage, erosion, or ulceration, with ulceration receiving a higher numerical score than submucosal hemorrha ge. A total score was assigned based on the sum of the scores from all regions. Comparisons among groups on each day were performed using th e Kruskal-Wallis test. Differences within a group among different time periods were determined using appropriate multiple comparisons. Signi ficant difference in mean gastroduodenal lesion score was found among all groups at 5, 14, and 30 days. Mean total score on days 5, 14, and 30 were as follows: group 1, 5.0, 5.2, 9.0; group II, 12.0, 12.7, 16.2 ; and group III, 26.0, 23.8, 21.5, respectively. Significant differenc es within a group among different time periods were found from days 0 to 5 in groups I and II, and from days 14 to 30 in group I. It was con cluded that misoprostol effectively decreased endoscopically detectabl e mucosal lesions in dogs given aspirin. (C) 1995 by the American Coll ege of Veterinary Internal Medicine.