Effect of cholecystokinin on pancreatic carcinogenesis in the hamster model.

To examine the effect of cholecystokinin (CCK) on pancreatic carcinogenicity in the hamster model, two sets of experiments were carried out. In one study, CCK (20 IDU/kg body wt) was given 3 h before, simultaneously with or 3 h after a single dose (20 mg/kg body wt) of N-nitrosobis(2-oxopropyl)amine (BOP). In another experiment, hamsters were treated similarly except that both CCK (20 IDU/kg body wt) and BOP (2.5 mg/kg body wt) were given weekly for 20 weeks. The results showed that CCK in the first experiment (single BOP dose) inhibited pancreatic cancer induction in a statistically significant fashion when given either 3 h prior to (P less than 0.05) or simultaneously with BOP (P less than 0.0005); however, CCK, when administered after BOP did not alter the cancer incidence as compared with hamsters treated with BOP alone. In the second experiment (chronic BOP treatment) the pattern and the incidence of pancreatic tumors were not affected by CCK.