Plasma concentrations of natriuretic peptides in patients on hemodialysis

The usefulness of plasma atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), and cyclic guanosine 3',5'- monophosphate (cGMP) as markers of fluid overload was examined in hemodialysis (HD) patients without diabetes mellitus. Plasma concentrations of ANP, BNP, CNP, and cGMP all decreased significantly during HD. Before HD, there was a strong correlation between plasma concentrations of ANP and those of BNP, and plasma concentrations of cGMP correlated significantly with those of all three natriuretic peptides. The cardiothoracic ratio also correlated significantly with plasma concentrations of ANP and those of BNP before HD. Systolic blood pressure correlated significantly only with plasma concentrations of CNP, both before and after HD. Changes in body weight during HD correlated only with those in plasma ANP; there was thus no correlation between changes in body weight and those in plasma CNP. In conclusion, only plasma ANP is a useful marker of the proper volume and dry weight of HD patients. Furthermore, CNP may participate in cardiovascular regulation in HD patients in a manner different from those of ANP and BNP.