Effect of experimental immune atrophic gastritis on the induction of gastric carcinoma by X-irradiation in ICR mice.

Divided doses of 6,000 or 8,000 rad of X-ray were given to the gastric region of ICR/JCL female mice with immune atrophic gastritis produced by the injection with allogenic stomach antigen. The carcinogenic effect of X-rays for inducing gastric carcinoma was significantly increased by this method. Two points can be presented as its reason. First, the pyloric gland mucosa regenerating from injuries by immunization was exposed to the divided dose of X-rays. Second, the marked requirement of gastrin secretion attributable to severe injuries of parietal cell mass by immunization and local X-irradiation acted as a promoting factor on the induction of gastric carcinoma by X-ray for a long time through the trophic effects on the pyloric gland.