APStracts 2:0391H, 1995.

Muscle chemoreflex causes renal vascular constriction. Mittelstadt, Scott W., Leonard B. Bell, Kathleen P. O'hagan, Jon E. Sulentic, and Philip S. Clifford. Departments of Anesthesiology and Physiology, Medical College of Wisconsin; and Veterans Affairs Medical Center, Milwaukee, Wisconsin 53295

APStracts 2:0391H, 1995.

The purpose of this study was to investigate the effects of the muscle chemoreflex on vascular conductance in innervated and denervated kidneys. During each experiment, six dogs ran at 10 km/hr for 8-16 min and the muscle chemoreflex was stimulated by reducing hindlimb blood flow (HLBF) (0%-80%) at 4 min intervals. Small reductions in HLBF did not cause changes in arterial blood pressure or renal vascular conductance. However, further reductions of HLBF caused increases in arterial blood pressure and decreases in renal vascular conductance. Decreases in renal vascular conductance occurred in the denervated kidneys when the HLBF was reduced below 1500+/-215 ml/min and in the innervated kidneys when HLBF was reduced below 1402+/-161 ml/min. There was not a significant difference between the reductions in HLBF required to cause a decrease in vascular conductance in the innervated and denervated kidneys. These results demonstrate that reductions in HLBF cause decreases in renal vascular conductance which are not dependent on renal sympathetic nerve activity.

Received 17 February 1995; accepted in final form 24 August 1995.
APS Manuscript Number H153-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 September 1995.