[Histological study on healing of cryocautery-induced rat gastric ulcer treated with T-593]

The effect of T-593, a novel anti-ulcer agent, on the healing of cryocautery-induced rat gastric ulcer was investigated histologically in comparison with that of famotidine. Seven days after ulceration, T-593 (30 mg/kg) or famotidine (30 mg/kg) was orally administered twice daily for 8 weeks. Two, 4 and 8 weeks after the start of administration, the ulcer size was measured by a stereoscopic microscope, and the gastric mucosa was observed histologically. The thickness of the regenerated mucosa, the density and the arrangement of gastric glands, the degree of inflammatory-cell infiltration in the submucosal tissue and the number of microvessels in the submucosal tissue were quantified. In macroscopical evaluation, T-593 and famotidine significantly accelerated ulcer healing, and the time courses of the ulcer index were similar in both cases. In histological evaluation of healed ulcers, T-593 normalized the thickness of regenerated mucosa and reduced the degree of inflammatory-cell infiltration and the number of microvessels in the submucosal tissue, while famotidine had no effect. In conclusion, T-593 possesses accelerating effects not only on the restoration of regenerated mucosa but also on the maturation of submucosal tissue. Therefore, T-593 improves the quality of ulcer healing.