Intrinsic regulation of the blood flow to the endocrine and exocrine parts of the rat pancreas.

To evaluate possible differences in the local regulation of blood flow between the endocrine and exocrine pancreatic parenchyma, the blood perfusion of the pancreas and the pancreatic islets has been measured after a 90-second period of anoxia or a 5-min period of increased venous pressure. After anoxia, caused by interruption of arterial blood flow, there was a significant increase (P less than 0.01) in islet blood flow (IBF) while whole pancreatic blood flow (PBF) remained unchanged. Arterial occlusion also increased the serum glucose (P less than 0.01) and serum insulin concentrations (P less than 0.001). Vagotomy prevented the increase in IBF but did not affect the increase in serum glucose or serum insulin concentration, which suggests that the increase in IBF was due to the increased serum glucose concentration. An increased venous pressure in the portal vein did not affect IBF, PBF, serum glucose or serum insulin concentrations. It is concluded that, in the rat pancreas, the local control of PBF and IBF is of minor importance in the regulation of blood flow.