NATRIURETIC PEPTIDE SYSTEM IN HUMAN HEART-FAILURE

Background. Atrial natriuretic peptide (ANP), brain natriuretic peptid e (BNP), and C-type natriuretic peptide (CNP) are a family of structur ally related peptides that participate in the integrated control of re nal and cardiovascular function. Previous studies suggest a functional role for these hormonal peptides in cardiorenal regulation in congest ive heart failure (CHF). Methods and Results. The present studies were performed in normal subjects (n=6) and in patients with mild (New Yor k Heart Association [NYHA] class I to II, n=20) and severe (NYHA class III to IV, n=20) CHF by use of radioimmunoassay and immunohistochemic al staining (IHCS). Plasma ANP was significantly increased in both mil d and severe CHF compared with normal subjects. In contrast, plasma BN P was only moderately increased in the severe CHF group, and plasma CN P concentration was unchanged in CHF compared with normal subjects. At rial tissue concentrations of the natriuretic peptides did not paralle l circulating concentrations. ANP predominated in normal atrial tissue , but BNP predominated in CHF. In ventricular tissue, IHCS staining wa s present for all three peptides in normal ventricular myocardium and was markedly enhanced in CHF. Conclusions. These studies support,a dif ferential regulation of ANP, BNP, and CNP circulating concentrations a nd tissue activity in human CHF.