[Relation between atrial natriuretic factor and the renin-angiotensin-aldosterone system in the renal reaction to acute volume loading in patients with essential hypertension].

Investigation of changes of the atrial natriuretic factor plasma concentration (ANF), plasma renin activity (PRA) and the plasma aldosterone concentration (PAC) and their correlation with the renal excretion of urine, sodium and potassium before and after infusion of 2 1 saline in the course of 2 hours in 6 controls and 7 patients with essential hypertension (EH) revealed the same rise of ANF in plasma of both groups (from 2.98 +/- 0.45 to 12.36 +/- 1.74 pmol/l in controls and from 3.80 +/- 0.72 to 15.78 +/- 2.06 pmol/l in EH), a comparable decline of PRA (from 0.91 +/- 0.419 to 0.256 +/- 0.127 nmol/l/hr in controls and from 1.711 +/- 0.324 to 0.714 +/- 0.185 nmol/l/hr in EH), and PAC (from 0.30 +/- 0.07 to 0.14 +/- 0.03 nmol/l in controls and from 0.53 +/- 0.13 to 0.24 +/- 0.06 nmol/l in EH). The comparable rise of plasma ANF concentration during infusion of saline was associated with a significantly higher renal excretion of urine and sodium in EH, as compared with controls. The authors conclude from these results that the ANF release into the blood stream after an acute volume overload in EH does not differ from controls. Thus the raised natriuresis in EH after a volume overload cannot be explained solely by the rise of ANF. Its renal action depends obviously on the interaction with many other haemodynamic and renal mechanisms, and as regards humoral factors, in particular on the interaction with the renin-angiotensin-aldosterone system. The inhibitory action of elevated ANF concentrations might participate in the suppression of PRA and PAC after a volume overload.