Enhancement by vaso-active intestinal peptide of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats.

The effects of vaso-active intestinal peptide (VIP) on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in Wistar rats given VIP every other day for 27 weeks after oral administration of MNNG for 25 weeks. In week 52, administration of VIP caused a significant increase in the incidence of gastric cancers, but did not influence their histological appearance. VIP significantly increased the labeling indices of the antral mucosa. Our findings indicate that VIP enhances gastric carcinogenesis, and that this effect may be related to its effect in increasing cell proliferation of the antral epithelial cells.