title: A radioimmunoassay for the measurement of tetrahydroaldosterone 3-glucosiduronic acid in human plasma.
abstract: A simple, reliable and specific radioimmunoassay procedure for the measurement of the principal aldosterone metabolite, tetrahydroaldosterone 3-glucosiduronic acid, in human plasma is described. The glucosiduronate is extracted from plasma (generally 200 microliter) by the use of Amberlite XAD-2 resin, eluted with acidic, aqueous ethanol, separated from unconjugated steroids by partition and estimated using a specific antibody. A disequilibrium system is used, but with a conventional charcoal separation; the advantages of such a system are discussed. Data obtained by incorporating chromatographic separations into the assay procedure is presented as evidence for the specificity of the method. Data concerning the long-term storage of plasma samples is given, together with plasma concentrations of the glucosiduronate in both normal people and in people with abnormalities of aldosterone secretion.
mesh_terms: D000450:Aldosterone / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism; D000818:Animals; D000917:Antibody Formation; D005260:Female; D005965:Glucuronates / Q000097:blood; D006801:Humans; D006929:Hyperaldosteronism / Q000097:blood; D008297:Male; D011817:Rabbits / Q000276:immunology; D011863:Radioimmunoassay / Q000379:methods*
chemical_list: D005965:Glucuronates; C013283:tetrahydroaldosterone 3 beta-glucosiduronic acid; D000450:Aldosterone