1984 Volume 37 Issue 4 Pages 369-372
The effects of dietary carbohydrate on the induction of gastric intestinal metaplasia by oral administration of N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) were observed with the rats raised on two different diets, viz, a starch diet (70% as starch) and a sucrose diet (46% of the total weight in the form of sucrose, 24% as starch). MNNG was administered at a concentration of 83μg/ml in drinking water for 3 months from 6 weeks old. Rats were examined at 3, 5, 7, 10 and 13 months after the start of MNNG administration.
Intestinal metaplasia detected as sucrase activity by tes-tape and tumors were induced in the glandular stomach at 5 months after MNNG administration in both dietary groups, and developed with aging. The incidence and sucrase activity of intestinal metaplasia were higher in the starch-fed rats than sucrose-fed rats. No tumor was found in the stomach without MNNG administration, but intestinal metaplasia was found with aging, although sucrase activity was lower than that of MNNG-administered rats in both dietary groups. The activities of maltase and sucrase in the proximal small intestine were slightly lower in MNNG-administered rats, but did not show any significant difference between starch and sucrose-fed rats. These results suggested that high starch intake involved in the early stage of the development of intestinal metaplasia as well as aging.
