[Healing promoting effect of proamipide, a novel drug that increases gastric defense mechanisms, on acetic acid-induced gastric ulcers in the rat].

The healing process of acetic acid-induced gastric ulcers was studied for over 180 days after ulcerogen injection, and the effect of a new antiulcer agent, proamipide, was also assessed by histological measurements. In the control group, rapid reduction in the macroscopic ulcer index and increment in histological indices such as healing, regeneration of defective mucosa and proliferation of granulation tissue were observed from the 5th day to the 60th day after the ulcer induction followed by significant aggravation on the 120th and 140th day, suggesting the recurrence or relapse of gastric ulcers may occur at about 120 to 140 days after acetic acid administration. Proamipide (20 mg/kg/day, p.o.) decreased all of these indices significantly from those in the control group. This indicates that proamipide remarkably promotes the healing process in acetic acid-induced gastric ulcers, the regeneration of the injured mucosa and also the formation of granulation tissue. The glandular index in the surrounding areas of the regenerated mucosa was lower than that in the central part in the control animals and this difference was decreased by proamipide intake, suggesting an imbalance in the regenerated mucosa of the scar may have significant roles in the induction of the recurrence or relapse of gastric ulcers.