Augmented synthesis of β-human atrial natriuretic polypeptide in human failing hearts

To elucidate the synthesis of atrial natriuretic polypeptide (ANP) in the failing heart, eighteen human right auricles obtained at cardiovascular surgery were studied. The concentration of α-human ANP-like immunoreactivity (α-hANP-LI) in human right auricles ranged from 13.8 to 593.5 μg/g, and the tissue α-hANP-LI concentration in severe congestive heart failure (CHF) (New York Heart Association (NYHA) functional class III or IV) was much higher than those in mild CHF of NYHA class I and class II. The α-hANP-LI in the human auricle consisted of 3 major components of ANP, γ-human ANP (γ-hANP), β-human ANP (β-hANP) and α-human ANP (α-hANP). The predominant component of α-hANP-LI was γ-hANP in the mild CHF, whereas β-hANP and/or α-hANP were prevailing in the severe CHF and, especially, β-hANP was markedly increased in human failing hearts.