1991 Volume 38 Issue 6 Pages 699-703
Plasma levels of immunoreactive atrial natriuretic peptide (IR-ANP) were measured with a specific radioimmunoassay in 19 undialysed patients with chronic renal failure. At the beginning, an extremely high level of plasma hANP (50 fmol/ml) seen in a patient was rejected with Smirnov's test and was excluded from further statistics. The plasma IR-ANP levels in these patients were significantly higher than those of 19 normal subjects matched with age and sex (10.9±1.6 vs 5.3±0.6 fmol/ml, mean±SEM, p<0.01), and positively correlated with mean blood pressure (r=0.44, p<0.05) and the cardiothoracic ratio (r=0.65, p<0.01), but did not correlate with creatinine clearance (r=-0.38, n.s.). Further, a significant correlation was observed between plasma IR-ANP and urinary protein output (r=0.47, p<0.05). On the other hand, urinary protein output did not correlate significantly with variables such as mean blood pressure, the cardiothoracic ratio or creatinine clearance. Since it has been suggested that ANP enhances glomerular capillary permeability, increased ANP responding to volume overload in those patients may play an important role in increasing urinary protein excretion.