[Experimental studies on gastric ulcer (5). Endoscopical evaluation of healing processes of acetic acid ulcer in rats (1). Ulcer reducing process].

The following results were obtained as the result of the sequential observations with an endoscope of the gastric ulcer produced by submucosal injection of acetic acid in rats. 1) The size of the ulcer produced by acetic acid injection observed on the 3rd day after ulcer induction depended on the concentration and volume of acetic acid. 2) The natural reducing rates of the size of ulcers in the region between the fundus and pylorus on the anterior wall (A) and in the glandular region on the greater curvature (B) were compared. The reducing rate of B ulcer was significantly faster than that of A ulcer. 3) No significant difference was observed in the reducing processes of untreated ulcers in 7 weeks old rats and 25 weeks old rats. 4) The ulcer reducing rate of female rats was found to be slightly faster than that of male rats. 5) The ulcer reducing rates of the aldioxa (ALD) and sucralfate (SUC) treated group were significantly faster than that of the control group. However, no difference in the ulcer reducing process between the cimetidine (CIM) treated group and the control group was observed. 6) The ulcer indices (UI) of both the combinations of ALD and SUC and of ALD and CIM were found to be significantly less than that of the control group on the 20th day. Treatment with drug combinations shortened the healing period of ulcers more than treatment with one drug alone. The percent healing by the combination of ALD and SUC was the highest among the groups treated. 7) An approximately linear relationship exists between the logarithm of the days after ulcer induction (x) and logarithm of UI (y), and the following equation was obtained: log y = a log x + b. Slope (a) indicates the ulcer reducing rate in evaluating the ulcer reducing process.