The effect of sex difference on induction of intestinal metaplasia in rats

Attempts were made to examine the sexual effects on the induction of intestinal metaplasia in rats. The number and locus of intestinal metaplasia in the gastric region induced by 2,000 rads of X-ray were greater in the male than in the female. Alkaline phosphatase activity appeared in the male only. The intestinal metaplasia induced by stomach antigen injection in the male persisted longer than in the female. Moreover, the incidence of intestinal metaplasia caused by whole body irradiation in ovariectomized rats was significantly higher than in the sham-ovariectomized ones. Therefore, it is likely that male sex hormones are promoting while female sex hormones are inhibiting the development of intestinal metaplasia.