The effect of cimetidine and 15(S) 15-methyl prostaglandin E2 on the healing of laser-induced gastric mucosal damage.

Delayed perforation, a complication of laser photocoagulation, could be reduced by accelerating healing and inhibiting gastric secretion. With the use of the Nd:YAG laser, a beam was passed through a single glass fiber (400 micrometer) with 10 degrees divergence at a constant power of 80 W for 1 sec at a 1-cm distance from the gastric mucosa. Rats were then randomly allocated to receive cimetidine (50 mg/kg), 15(S)15-methyl prostaglandin E2 (50 micrograms/kg), or saline intraperitoneally twice daily for 4 or 7 days. The surface area of ulceration at 4 days for the control rats and the cimetidine- and prostaglandin-treated rats was 29, 34, and 28 mm2, respectively, and was much larger than the initial lesion of 15 mm2. Histologically, all lesions showed the typical appearances of peptic ulceration with perforation in half the prostaglandin-treated rats. By 7 days, the surface area in the cimetidine-treated rats appeared to decrease, but the light microscopic changes were similar to the saline- and prostaglandin-treated rats. Neither cimetidine nor prostaglandin enhanced healing in this study.