Increased sensitivity of the renal vasculature to adenosine in streptozotocin-induced diabetes mellitus rats. Pflueger, Axel C., Friedemann Schenk, Hartmut Osswald. Department of Pharmacology, Faculty of Medicine, University of Tuebingen, D-72074 Tuebingen, Germany
APStracts 2:0065F, 1995.
Adenosine (ADO) has been implicated as a pathophysiologic factor in contrast media (CM)-induced acute renal failure, which was suggested to be encountered more often in patients with diabetes and impaired renal function [6, 8, 11, 27]. Therefore, we studied the renal vascular response to exogenous and endogenous ADO in streptozotocin -induced diabetic rats.We found that exogenous ADO (0.01-100 nmol) injected into the abdominal aorta decreased renal blood flow (RBF) in a dose dependent manner. The dose response curve was shifted to the left by factor 30 in diabetic compared to nondiabetic rats. Renal vascular response to endogenous ADO, assessed by postocclusive reduction of RBF after a 30 second renal artery occlusion, was significantly enhanced (p<0.001) in diabetic (75.6+/-3.9 %), compared to nondiabetic rats (36.5+/-2 %). Adenosine-A1 receptor blockade (DPCPX) attenuated exogenous and endogenous ADO-induced renal vasoconstriction in both groups. We conclude that the ADO-A1 receptor signal-transduction chain is altered in diabetic animals, and that the enhanced vasoconstrictive action of ADO could be involved in the kidney pathophysiology of diabetes mellitus.

Received 31 January 1995; accepted in final form 18 April 1995.
APS Manuscript Number F29-5.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on  2 May 1995.