Natriuretic peptides in heart failure

Representation of the effects of elevated plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in severe heart failure. ANP and BNP may increase (+) the rate of sodium excretion and reduce (-) the effects of the renin-angiotensin (RAS), sympathetic nervous systems (NS), and endothelin (ET)-1; the net effect of these actions is reduced preload and afterload. A similar elevation in inducible nitric oxide synthase (iNOS) is seen in humans with severe heart failure. These initially homeostatic mechanisms paradoxically contribute to the pathophysiology of the failing myocardium.