SYNTHETIC RAT ATRIAL NATRIURETIC FACTOR INHIBITSIN VITROANDIN VIVORENIN SECRETION IN RATS

Abstract

The action of a synthetic rat atrial natriuretic factor (ANF) with 28 amino acids on renin secretion in rats was investigated. Renin release by kidney cortex slices was determined after 90 min of incubation at 37.degree. C. ANF inhibited basal renin release in a dose-related fashion. ANF also decreased cAMP release and increased cGMP release in a dose-dependent manner. Renin release stimulated by 10-7 M isoproterenol was inhibited by ANF with an ID50 [median inhibitory dose] of 5.8 .times. 10-8 M. The renin-inhibitory effect was not Ca-dependent. In anesthetized rats, a bolus i.v. dose of ANF decreased plasma renin activity and cAMP concentration, but increased cGMP concentration. ANF inhibits renin secretion via the direct action on juxtaglomerular cells, and this effect may be partly mediated by the change in cyclic nucleotide production.