Plasma aldosterone by radioimmunoassay, determination in normal man and in patients on maintenance haemodialysis

Olgaard, K. Plasma Aldosterone by Radioimmunoassay Determination in Normal Man and in Patients on Maintenance Haemodialysis. Scand. J. clin. Lab. Invest. 35, 31–39, 1975.The plasma aldosterone concentration was measured by a radioimmunoassay in which paper chromatography was used for separation of the steroids. The method had a low blank value (1.3 ± 2.8 pg/ml), and the sensitivity was 6 pg/ml. The variation coefficients for interassay and intraassay determinations were 13.0% and 9.4%, respectively. An accuracy study on fixed amounts of unlabelled aldosterone added to pool-plasma gave a linear correlation (slope = 0.9973). In a normal material, the mean plasma aldosterone concentration was found to be 120 pg/ml. In 26 patients on maintenance haemodialysis the mean plasma aldosterone concentration was 68 pg/ml, in the group of anephric patients 36 pg/ml, and in the non-nephrectomized group 91 pgiml. There was a significant difference (P < 0.01) between the two groups as well as between the total group of p...