Influence of oral supplementation of ascorbate upon the induction of N-methyl-N'-nitro-N-nitrosoguanidine.

Influence of mega-ascorbate (AsA) intake upon the induction of gastric cancer of rats was investigated. By feeding the ascorbate-supplemented diet, though the incidence of gastric cancer was not effectively inhibited, the infiltrative growth was significantly repressed. Mega-ascorbate intake was more beneficial in alleviating the development of gastric cancer when it was commenced after the middle of long-term experimental period (initiation of adenomatous hyperplasia but no appearance of malignant lesions) rather than from the beginning of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) drinking. A remarkable effect of mega-ascorbate intake was to reinforce the surrounding connective tissues to retard the malignant growth.