Plasma concentrations of atrial natriuretic peptide in various diseases.

Using a radioimmunoassay for atrial natriuretic peptide (ANP) we studied plasma concentrations of immunoreactive ANP in order to investigate the pathophysiological role of ANP in patients with various diseases. Plasma ANP levels were elevated in patients with congestive heart failure (394 +/- 260 pg/ml, n = 8) and chronic renal failure (219 +/- 86 pg/ml, n = 11). In patients undergoing hemodialysis plasma ANP levels were markedly high and decreased after hemodialysis from 433 +/- 166 pg/ml to 204 +/- 92 pg/ml (n = 11). ANP was removed from blood to dialysate (21 +/- 13 pg/ml of dialysate, n = 6, dialysate flow: 500 ml/min). Plasma ANP level was conversely correlated with creatinine clearance (r = -0.812, p less than 0.001) in patients with renal diseases (n = 29). In patients with atrial fibrillation, pace maker implantation, lung disease, chronic glomerulonephritis, nephrotic syndrome, essential hypertension, liver disease and cerebrovascular disease, plasma ANP levels were not significantly different from those in normal subjects (70 +/- 32 pg/ml, n = 28). These results suggest that ANP may be a circulating hormone playing pathophysiological roles in congestive heart failure and chronic renal failure.