AJP - Renal Physiology, Vol 249, Issue 1 49-F53, Copyright © 1985 by American Physiological Society
Atriopeptins: correlation between renal vasodilation and natriuresis
K. Wakitani, B. R. Cole, D. M. Geller, M. G. Currie, S. P. Adams, K. F. Fok and P. Needleman
The effect of atrial peptides on renal function was studied in intact
anesthetized dogs. A quantitative comparison of bolus intra-arterial
injections demonstrated a rank order potency as renal vasodilators and
natriuretic/diuretic agents as follows: ser-leu-arg-arg-atriopeptiin III
(SLRR-APIII) greater than high molecular weight artrial peptide greater
than or equal to atriopeptin (AP)III = APII much greater than API
(essentially inactive). A sustained infusion of APIII was employed in order
to study the temporal and quantitative correlation of the renal functional
changes induced by the atrial peptide. Both intra-arterial and intravenous
administration of the peptide produced concentration-dependent increases in
renal blood flow, urine volume, sodium excretion, and osmotic clearance.
Infusion of APIII into the renal artery did not alter systemic blood
pressure or heart rate. Intravenous infusions of APIII required 10 times
higher doses to induce the changes in renal vascular resistance and
electrolyte excretion, and a fall in blood pressure and tachycardia
resulted. The natriuretic-diuretic effect of the atriopeptins appears to be
closely associated with renal vasodilation, exhibiting a positive linear
correlation between the peptide-induced changes in sodium excretion and
changes in renal blood flow.
