Plasma atrial natriuretic peptide in patients with chronic renal failure
Chen, J.H.; Tsai, J.H.; Lai, Y.H.; Hwang, S.J.
Journal of the Formosan Medical Association 89(8): 645-650
1990
ISSN/ISBN: 0929-6646 PMID: 1981224 Document Number: 356586
Plasma atrial natriuretic peptide (ANP) levels were measured in non-dialyzed and dialyzed chronic renal failure (CRF) patients and in normal subjects. Changes in plasma ANP in response to hemodialysis (HD) and to isolated ultrafiltration (UF) were also investigated in dialyzed CRF patients. Plasma ANP levels were significantly higher in 28 non-dialyzed CRF patients than in 27 normal subjects (mean .+-. SEM, 174.0 .+-. 25.9 vs 25.0 .+-. 1.9 pg/ml, p < 0.001). Plasma ANP levels did not correlate with blood urea nitrogen or serum creatinine, however patients with advanced renal failure (creatinine clearance < 10 ml/min) with cardiomegaly (cardiothoracic ratio > 50%) or hypertension (BP > 140/90 mm Hg) had significantly higher plasma ANP levels than those who were not. A 6-hour HD significantly decreased the plasma ANP level (423.4 .+-. 71.3 to 220.6 .+-. 40.0 pg/ml, p < 0.001) and body weight in 21 dialyzed CRF patients, and the decrement in plasma ANP showed a positive correlation with the decrement in body weight (r = 0.425, p = 0.056). In 8 dialyzed CRF patients, we further performed a 1-hour isolated UF for removal of isoosmotic intravascular fluid without changes in the solute concentrations, followed by a subsequent 5-hour HD. The decrease in plasma ANP during the 1-hour UF period was 68% of the total ANP decrement for the whole 6-hour study. The average plasma ANP level was decreased with 94.6 .+-. 42.5 pg/ml/kg/h in the UF period compared to 3.5 .+-. 1.4 pg/ml/kg/h in the HD period (p < 0.001). This indicates that removal of volume from the intravascular compartment, and not the dialysate loss of ANP, is the main cause for the decrease of plasma ANP in hemodialysis treatment. The results support the findings that the increase in plasma ANP in patients with CRF is mainly due to plasma volume expansion.