Effects of renal denervation on the cardiovascular response to furosemide in conscious lambs. Smith, Francine G., and Andrew M. Strack. Department of Medical Physiology, The University of Calgary, Calgary, Alberta, CANADA, T2N 4N1
APStracts 2:0043H, 1995.
The cardiovascular response to furosemide in the newborn, and the role of renal sympathetic nerves in influencing this response have not been investigated. We hypothesized that in conscious lambs, furosemide would decrease blood pressure, the response being accentuated in the absence of renal sympathetic nerves. Pulsatile pressures and heart rates were measured before and after furosemide (2 mg/kg) administration to chronically instrumented lambs with either bilateral renal denervation (denervated, n=8), or renal nerves intact (intact, n=6). In intact lambs, mean arterial pressure remained constant after furosemide; in denervated lambs, there was an increase in arterial pressure 20 min after furosemide (p<0.001); control levels were reached by 100 min. Basal heart rate was higher in denervated than in intact lambs (p=0.009). In both groups of lambs, heart rate increased 40 min after furosemide and remained elevated. These data provide new information that, in conscious newborn animals, renal sympathetic nerves influence the blood pressure response to furosemide, as well as basal control of heart rate.

Received 11 October 1994; accepted in final form 6 February 1995.
APS Manuscript Number H905-4.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 24 February 1995.