AJP - Renal Physiology, Vol 244, Issue 6 659-F665, Copyright © 1983 by American Physiological Society
Renal nerve responses to cardiac receptor stimulation with bradykinin in monkeys
A. J. Gorman, I. H. Zucker and J. P. Gilmore
Previous data from our laboratory demonstrated a species difference between
the cat and dog in the arterial blood pressure (ABP) and renal nerve
activity (RNA) responses to epicardial bradykinin (BK) applications. The
present study was carried out to determine the ABP and renal nerve
responses to chemical activation of cardiac afferents by BK in the intact
and sinoaortic-denervated and vagotomized (SAD + VX) nonhuman primate.
Seven Macaque monkeys (fascicularis and nemestrina) anesthetized with
pentobarbital or chloralose were used in this study. The heart was exposed
and suspended in a pericardial cradle. A left atrial (LA) catheter was
inserted through the appendage. Changes in ABP and RNA (percent change from
control) were determined when 1 and 10 micrograms/ml BK (in 1-ml volume)
were applied to the anterior surface of the left ventricle or injected into
the LA (0.3 and 3.0 micrograms/kg BK) in the intact and SAD + VX state. In
both the intact and SAD + VX monkeys, ABP and RNA were significantly
reduced with epicardial BK. In the intact state, LA injections of BK
produced a significant decrease in the % delta of RNA and a depressor
response. In the SAD + VX monkey, significant hypotensive responses were
also observed with LA injections of BK concomitant with significant
reductions in RNA. These results show the existence of a depressor response
and inhibition of renal sympathetic nerve activity in the nonhuman primate
mediated by the action of bradykinin on cardiac sympathetic afferents.
