title: [A method for quantitative dertermination of 20-keto steroids in urine during the use of a 3 alpha-, 20 beta-hydroxysteroid: NAD oxidoreductase (author's transl)].
abstract: A method is described for the quantitative determination of 20-ketosteroids in urine during the application of a 3alpha, 20beta-hydroxysteroid: NAD oxidoreductase. In the presence of NADH H+ the enzyme catalyses in an "equimolar" developing reaction the reduction of 20-keto groups of C-21 steroids giving 20 beta-alcohols. The measurable NADH H+ consumption is a measure for the quantity of those 20-ketosteroids present in the reaction mixture. The 3alpha-hydroxysteroid: NAD oxidoreductase activity of the enzyme does not influence the specificity of the method to determine the 20-ketosteroids because,-under the present extraction and purification conditions-those 3alpha-hydroxy-5alpha-androstan derivatives are not reaching the reaction mixture of determination. The demands towards the criterions of reliability (correctness and exactitude) come to be fulfilled by this method.
mesh_terms: D000293:Adolescent; D000328:Adult; D001192:Arylsulfatases; D002021:Buffers; D055598:Chemical Phenomena; D002621:Chemistry; D004796:Clinical Enzyme Tests; D005260:Female; D005966:Glucuronidase; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006914:Hydroxysteroids; D007664:Ketosteroids / Q000652:urine*; D008297:Male; D008722:Methods; D009247:NADH, NADPH Oxidoreductases; D014556:Urine
chemical_list: D002021:Buffers; D006914:Hydroxysteroids; D007664:Ketosteroids; D009247:NADH, NADPH Oxidoreductases; D001192:Arylsulfatases; D005966:Glucuronidase
vernacular_title: Quantitative Bestimmung von 20-Ketosteroiden im Urin mit Hilfe einer 3alpha, 20beta-Hydroxysteroid: NAD-oxido-reduktase