Novel method for producing standard subacute gastric ulcer in rats and for the quantitative evaluation of the healing process. Effect of several drugs on healing.

A simple new method has been developed for producing subacute gastric ulcers in rats, and it has been combined with a novel method for the quantitative evaluation of the healing process. Fasted rats of body weight 120-150 g were used. The animals were anaesthesized by ether and then a polyethylene catheter was orally inserted in the stomach with a fine needle inside. After the cannula reached the gastric wall, the needle was pressed gently so as to punch the tastric wall. Drugs under study were administered orally 30 min and 24 hr after the puncture. Food and water were given ad libitum from 2 hr after the intervention until the end (96 hr) of experiments. In order to follow the healing process of subacute ulcer, the so-called tensile strength of the ulcer was determined by inflating and was expressed in mmHg. The healing rate was calculated. The antiulcer drugs, cimetidine, famotidin, pirenzepine, and sucralfate, dose dependently and significantly increased the healing rate of ulcer. Nonsteroidal antiinflammatory drugs, naproxen, piroxicam, indomethacin, and ibuprofen, significantly delayed the healing of ulcer and acetylsalicylic acid showed no significant effect on the healing. Strong HCl (0.5 molar) significantly delayed the healing of ulcer. N-EM given subcutaneously dose dependently delayed the healing of subacute ulcer.