The 5α-reduction of radioactive Δ4-3-ketosteroids, which do not contain substitutions on carbon-11 of the steroid molecule, is followed in the presence of an excess of NADPH by measuring the appearance of the radioactive 5α-reduced metabolites, utilizing a rapid thin-layer chromatographic separation. The assay in this chapter has been developed because the low activity of the enzyme in most tissues precludes the measurement of NADPH disappearance spectrophotometrically. The enzyme exhibits distinctive tissue localization in that most activity is found in the organs of accessory reproduction and in liver.
ASJC Scopus subject areas
- Molecular Biology