Hemodynamic response of the pancreas to synthetic chicken VIP in dogs

The effects of synthetic chicken VIP (an octacosapeptide corresponding to the entire sequence of chicken VIP) on pancreatic blood flow and on systemic arterial pressure was examined in dogs. The relationship between pancreatic blood flow and systemic arterial pressure in response to synthetic chicken VIP was also investigated. Pancreatic blood flow increased promptly and significantly with exogenous synthetic chicken VIP. Synthetic chicken VIP administered in graded doses resulted in dose-dependent increases in both the peak rate of the pancreatic blood flow and the duration of the response of the pancreatic blood flow. Graded doses of synthetic chicken VIP also elicited both a graded increase in the systemic systolic pressure and a decrease in the systemic diastolic pressure. Therefore, synthetic chicken VIP given in graded doses resulted in a dose-dependent augmentation of the maximum pulse pressure. Pancreatic blood flow increased despite a fall in the systemic arterial pressure in response to synthetic chicken VIP. This increase in blood flow lasted significantly longer than the changes in the systemic arterial pressure. It was clarified in this study that synthetic chicken VIP has a biological effect on both the pancreatic blood flow and the systemic arterial pressure. The results of our experiments also suggest that synthetic chicken VIP itself may directly induced vasodilatation of the local vessels in the pancreas.