Atrial natriuretic factor reduces renin release by opposing alpha-adrenoceptor activity.
To examine how atrial natriuretic factor (ANF) inhibits renin release during renal sympathetic nerve stimulation, experiments were performed in barbiturate-anesthetized dogs. In five dogs, intravenous ANF infusion (50 ng.min-1.kg body wt-1) reduced renin release induced by renal nerve stimulation (1 Hz) from 16.8 +/- 8.4 to 3.5 +/- 2.1 micrograms angiotensin I (ANG I)/min. In two groups, renin release was raised by ureteral occlusion, which enhances the effects of beta-adrenoceptor stimulation and increased prostaglandin synthesis. During ureteral occlusion, intrarenal infusion of isoproterenol (0.2 micrograms.min-1.kg body wt-1) increased renin release in eight dogs to 82.6 +/- 10.9 micrograms ANG I/min, which was not significantly reduced by ANF infusion (81.1 +/- 10.1 micrograms ANG I/min). Similarly, intrarenal infusion of arachidonic acid (80 micrograms.min-1.kg body wt-1) during ureteral occlusion increased renin release in five dogs to 22.2 +/- 3.0 micrograms ANG I/min, which was not significantly reduced by ANF infusion (22.5 +/- 3.5 micrograms ANG I/min). Finally, in six dogs examined at free urine flow, intrarenal infusion of phenylephrine, an alpha-adrenergic agonist, raised renin release from 0.5 +/- 0.3 to 20.1 +/- 6.8 micrograms ANG I/min, which was reduced to 10.6 +/- 3.9 micrograms ANG I/min by intravenous ANF infusion (100 ng.min-1.kg body wt-1). These results indicate that ANF does not counteract stimulation of renin release by beta-adrenoceptors and prostaglandins but reduces nerve-stimulated renin release by opposing alpha-adrenoceptor activity.
Institute for Experimental Medical Research, University of Oslo, Ullevaal Hospital, Norway.
P A
PA
Naess
G
G
Christensen
F
F
Kiil
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D003250:Constriction; D004285:Dogs; D004558:Electric Stimulation; D005260:Female; D007262:Infusions, Intravenous; D007545:Isoproterenol / Q000494:pharmacology; D007668:Kidney / Q000294:innervation; D008297:Male; D009424:Nervous System Physiological Phenomena; D010656:Phenylephrine / Q000494:pharmacology; D012083:Renin / Q000378:metabolism*; D014513:Ureter / Q000502:physiology
D000317:Adrenergic alpha-Antagonists; D001095:Arachidonic Acids; D010656:Phenylephrine; D016718:Arachidonic Acid; D009320:Atrial Natriuretic Factor; D012083:Renin; D007545:Isoproterenol