A Non-Chromatographic Non-Extraction Radioimmunoassay for Serum Aldosterone

Abstract

A direct radioimmunoassay for serum aldosterone was developed using a highly specific sntibody and 8-anilino-1-naphthalene sulfonic acid as a blocking agent to inhibit the binding of aldosterone to serum proteins. 125I-labeled aldosterone was used as the labeled antigen and polyethylene glycol was used to separate antibody-bound and free aldosterone. The minimum detectable concentration was 1.5 pg/tube. There were excellent correlations between the present method and other methods, i.e., 1) a method using tritiated aldosterone, 2) a method using dichloromethane extraction before assay, and 3) a commercial kit method. The intra-assay coefficient of variation was 6.9%, and the inter-assay coefficient of variation was 10.7%. The values found in normal human serum were comparable with those reported using other methods. The present radioimmunoassay eliminates both extraction of aldosterone from serum and chromatographic separation and requires only 0.1 ml of serum for assay.

Comparison of the renal effects of angiotensin converting enzyme inhibitor and calcium antagonist in hypertensive Type 2 (non-insulin-dependent) diabetic patients with microalbuminuria: a randomised controlled trial

“…Serum total protein concentration was measured in an Auto-Analyzer (SMAC I, Technicon, Tarrytown, NY, USA). PRA [24], PAC [25] and urinary albumin (normal range 0.3-13.4~tg/min [26] were measured by the respective radioimmunoassay. Hblc was measured by high-performance liquid chromatography [27] on a cation-exchange minicolumn (Auto Alc HA-8110, Kyoto Daiichi Kagaku, Kyoto, Japan) (normal range 3.3-5.2% of total).…”

Effect of alacepril on blood pressure and neurohumoral factors at rest and during dynamic exercise in patients with essential hypertension.

“…with PEG method (Morimoto et al, 1983), and PA by Aldosterone-r.i.a. kit II (Ogihara et al, 1977). Plasma NA and A were assayed by h.p.l.c.…”

Insulin sensitivity with respect to glucose metabolism in hypertension-prone men did not predict the blood pressure increase in 5 years

“…12 Plasma values of aldosterone were determined with radioimmunoassay techniques. 13 The study protocol was approved by the Ethics Committee, Medical Faculty of Lund University, and informed consent was obtained from each individual. This first investigation comprised 39 relatives and 29 controls.…”