The reduction of renin and aldosterone as a response to acute hypervolemia is blocked by a monoclonal antibody directed against atrial natriuretic peptides.

We have previously reported that the strong diuresis, natriuresis and urinary cyclic GMP excretion after acute volume loading in rats are caused by ANP and can be blocked by additionally given monoclonal antibodies directed against ANP. The present report describes that in contrast to the changes in ANP and cyclic GMP, the plasma renin activity and aldosterone concentration are decreased after volume loading. This decrease is completely blocked by simultaneous administration of the monoclonal antibodies. Plasma cyclic AMP levels are not affected. From this study it seems to be clear that the inhibition of the renin-aldosterone system is not a direct effect of volume expansion but is specially mediated by the released ANP.