Neural influences on the renal response to acute volume expansion
in rats with heart failure.
Patel, Kaushik P., Ping L. Zhang, and Pamela K. Carmines.
Department of Physiology and Biophysics, University of Nebraska
Medical Center, Omaha, Nebraska 68198-4575
APStracts 3:0244H, 1996.
Experiments were performed to test the postulate that neural
influences underlie the suppressed excretory response to acute volume
expansion (VE) typically observed 3-4 weeks after myocardial
infarction to induce chronic heart failure (CHF). Responses to VE
were assessed in innervated (intact) and denervated (DNX) kidneys of
anesthetized CHF rats and sham-operated controls. CHF rats exhibited
blunted natriuretic responses to VE in both intact kidneys (35% of
sham response) and DNX kidneys (55% of sham DNX response). CHF rats
also displayed suppressed excretory responses to atrial natriuretic
factor (ANF, 0.25 [mu]g x kg-1 x min-1 iv) in both intact kidneys
(74% of sham response) and DNX kidneys (63% of sham DNX response).
Additional experiments confirmed that the compliance of the veno
-atrial junction did not differ between sham rats (52 +/- 2
mmHg/[mu]l) and CHF rats (54 +/- 2 mmHg/[mu]l). The observations
support the contention that both tonic renal sympathetic renal nerve
activity and suppressed renal ANF responsiveness likely contribute to
the blunted excretory response to VE during CHF.
Received 21 December 1995; accepted in final form 21 March 1996.
APS Manuscript Number H1193-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 17 June 96