Influence of adrenaline on blood perfusion and vascular conductance of the whole pancreas and the islets of Langerhans in the rat.

The blood perfusion and vascular conductance of the whole pancreas and of the islet organ were measured separately with the aid of a microsphere technique after intravenous infusion (0.1 ml/min) of adrenaline in different doses (1, 2 or 3 micrograms/kg body weight x min). Control animals were infused with saline alone and had a mean arterial blood pressure of approximately 100 mm Hg. Adrenaline increased the mean arterial blood pressure to 150, 175 and 200 mm Hg, respectively. A decrease of both whole pancreatic blood flow and islet blood flow could be seen after adrenaline administration, but no differences were observed between the two highest doses (greater than 2 micrograms/kg body weight x min of adrenaline). The fraction of blood diverted through the islets was approximately 10% of the whole pancreatic blood flow in all experimental groups. Also the vascular conductance decreased more than the blood perfusion values. It is concluded that adrenaline produces a decrease of blood flow to both the islets and the whole pancreas, which is similar in both the endocrine and exocrine tissue.