The adipocyte-specific cytokine adiponectin, has cardioprotective effects, correlates with endogenous cardiac natriuretic peptides and adipocyte has guanylyl cyclase-A receptors of natriuretic peptides. To evaluate the effect of carperitide (atrial natriuretic peptide; ANP) on plasma adiponectin in patients with heart failure. Seventy-five patients admitted to our hospital with decompensated heart failure were randomised (1:2) to nitroglycerin (group I: n = 23) or carperitide infusion (group II: n = 52). Blood samples were collected at baseline and after 7 days. Plasma levels of total and high-molecular weight (HMW) adiponectin, ANP and brain natriuretic peptide (BNP) were measured. There were no differences in baseline characteristics between the two groups. In group I, plasma levels of total and HMW adiponectin were significantly decreased (21.1+/-2.5 to 18.6+/-2.5 microg/mL, p<0.05, 12.3+/-1.8 to 10.8+/-1.7 microg/mL, p<0.05, respectively) concomitant with the decrease in plasma levels of ANP and BNP. In group II, plasma levels of total and HMW adiponectin were significantly increased (17.3+/-1.3 to 19.7+/-1.6 microg/mL, p<0.0001, 9.8+/-1.0 to 10.5+/-1.0 microg/mL, p<0.05, respectively) concomitant with the increase in ANP. These findings indicate that carperitide infusion increases plasma levels of total and HMW adiponectin in patients with heart failure.