Effects of antiulcer agents on healing of mepirizole-induced duodenal ulcers in rats.

Healing processes of duodenal ulcers induced by mepirizole and effects of several drugs on the ulcer healing were studied in rats. Mepirizole-induced duodenal ulcers, except for the perforated ones within 3 days after ulceration, gradually diminished in size and depth by the 15th day. Several ulcers persisted for up to 40 days, but complete healing in all rats occurred by the 60th day after ulceration. Oral cimetidine and YM-11170 (both histamine H2-receptor antagonists), at 200 and 30 mg/kg twice daily for 10 days, respectively, significantly accelerated the healing of duodenal ulcers. Oral Maalox (antacid) at 1,000 mg/kg thrice daily and propantheline (anticholinergic agent) at 30 mg/kg twice daily tended to accelerate the healing of the ulcers. Oral 16,16-dimethyl PGE2, at 0.03 and 0.1 mg/kg twice daily, resulted in a delayed healing of the ulcers. Mepirizole-induced duodenal ulcers appear to be a useful model for the study of ulcer healing and for screening of antiulcer drugs.