Control of O2 supply to the pancreas during a cholecystokinin-induced increase in metabolism.

In the anesthetized dog, the pancreatic excretion of enzymes and the pancreatic blood flow were stimulated by a cholecystokinin (CCK) shot of 1 U/kg iv. The question raised was: is this augmented blood flow a metabolically controlled hyperemia or is it independent of the metabolic performance. After the administration of CCK, blood flow as well as O2 consumption were increased, while O2 extraction initially remained unchanged but later it increased. Capillary density, mitochondrial O2 consumption, capillary PO2 and cellular PO2 were calculated, using the model of the metabolic control of tissue oxygenation. The changes mentioned above could be simulated rather exactly. These simulations revealed that during the CCK stimulation of the pancreas is able to control its O2 supply through a fast decrease of the arteriolar resistance and a slow capillary recruitment. Thus, by a metabolic control the oxygen is sufficiently supplied to the pancreatic tissue.