Effect of cimetidine and omeprazole on gastric ulcer healing of rats with limited food intake time.

The effects of cimetidine, omeprazole and atropine sulfate on the healing of acetic acid-induced gastric ulcers in rats with limited food intake time (9:00-10:00 a.m. and 5:00-6:00 p.m.) were evaluated 15 days after the acid injection. Oral repeated administration of cimetidine (25-100 mg/kg twice daily) or omeprazole (10-50 mg/kg once daily) dose dependently accelerated ulcer healing. Atropine sulfate (10 mg/kg twice daily, p.o.) was ineffective. A single oral administration of omeprazole (50 mg/kg) or cimetidine (100 mg/kg) resulted in potent and long-lasting anti-acid secretory and gastrin-releasing actions. The degree and duration of anti-acid secretion by atropine sulfate were equal to those of cimetidine, but the elevation of gastrin release by atropine sulfate was weak and temporary. These results indicate that the gastric ulcers of rats with a limited food intake time are useful for evaluating the healing effects of cimetidine and omeprazole on gastric ulcers. In addition, the effects of both drugs may be related to the increased gastrin release rather than to the reduced acid secretion.