Impaired aldosterone production by chronic intravenous infusion of atrial natriuretic factor in rabbits

This study assessed the effect of chronic infusions of atrial natriuretic factor (ANF) on in vivo and in vitro production of aldosterone. Male New Zealand white rabbits were intravenously infused for 5 days with either vehicle (0.9% NaCl solution) or rat ANF (99-126) at 100 ng/kg per h. In ANF-infused rabbits plasma ANF levels increased 2.7-fold, plasma renin activity (PRA) was reduced and plasma aldosterone, but not blood pressure, responses to exogenous angiotensin II (Ang II) were attenuated. In adrenal capsular cells isolated from rabbits chronically infused with ANF, maximal aldosterone responses to adrenocorticotrophic hormone, Ang II and potassium were significantly reduced without any changes in sensitivity. These results suggest that chronic small increases in circulating ANF can blunt aldosterone responses to various aldosterone secretogogues without inhibiting the pressure response to Ang II.