Effects of raw soya diet and cholecystokinin receptor blockade on pancreatic growth and tumor initiation in the hamster.

Raw soya diet in the hamster had short-term trophic effects on the pancreas, causing significant increases in pancreatic weight, DNA, RNA, and protein. These changes appear to be mediated by cholecystokinin (CCK) because the increases were blocked by infusion of the CCKA receptor antagonist, MK329. Raw soya diet significantly increased plasma levels of CCK in both the short-term and long-term studies. However, raw soya did not potentiate pancreatic cancer in hamsters treated with N-nitrosobis(2-oxopropyl)amine (BOP). Infusion of MK329 during the initiation period of carcinogenesis did not change tumor incidence or yield, suggesting that endogenous CCK does not influence tumor induction during the initiation period in the hamster.