Stimulation of renin secretion by no-donors is related to the cyclic-amp pathway. Kurtz, Armin, Karl-Heinz G[diaeresis]otz, Marlies Hamann, Martin Kieninger, Charlotte Wagner. Institut f[umlaut]ur Physiologie der Universit[umlaut]at Regensburg, Germany
APStracts 5:0014F, 1998.
This study aimed to characterize the cellular pathways along which nitric oxide influences the secretion of renin from the kidney. Using the isolated perfused rat kidney model we found that the NO-donor sodium-nitroprusside (SNP) (1-30 (mol/l) induced a prompt concentration dependent 4-fold increase of basal renin secretion. The membrane permeable cGMP analogues 8-bromo-cGMP and 8-pCPT cGMP (5 -50(mol/l) inhibited basal renin secretion and attenuated the stimulation of renin secretion by SNP. Conversely, the renin stimulatory effect of SNP was enhanced in the presence of the G -kinase inhibitor Rp-8CPTcGMPS (10(mol/l) The renin stimulatory effect of SNP was amplified in nominally calcium free perfusate and was abolished in the presence of angiotensin II (1nmol/l). Renin secretion stimulated by SNP was clearly attenuated by the A-kinase inhibitor Rp-8CPTcAMPS (25(mol/l). These findings indicate that the renin stimulatory effect of NO-donors in renal juxtaglomerular cells cannot be explained by activation of G-kinase and is also less likely to be causally related to the regulation of renin secretion by calcium. Since A-kinase activity is required for the stimulation of renin secretion by SNP it appears as if the renin stimulatory effect is causally related to the cAMP pathway controlling renin secretion.

Received 7 May 1997; accepted in final form 5 January 1998.
APS Manuscript Number F154-7.
Article publication pending Am. J. Physiol. (Renal Physiology).
ISSN 1080-4757 Copyright 1998 The American Physiological Society.
Published in APStracts on 28 January 1998