title: 3 alpha, 3 beta and 17 beta-hydroxysteroid dehydrogenase activities in the cytoplasmic and microsomal fractions of human liver.
abstract: Optimized assay systems for the determination of cytoplasmic and microsomal 3 alpha-, 3 beta-, and 17 beta-hydroxysteroid dehydrogenase (HSDH) activities in human liver have been developed. Using these methods the activities of cytoplasmic 3 alpha-, 17 beta-, and microsomal 3 alpha- and 3 beta-HSDH were measured in cell fractions prepared from liver biopsies from 17 patients who showed no signs of endocrinologic disturbances. The means and standard deviations (SD) of these four activities (nmol/min/mg protein) were as follows: cytoplasmic 3 alpha-HSDH, 1.03 +/- 0.34; cytoplasmic 17 beta-HSDH, 0.365 +/- 0.129; microsomal 3 alpha-HSDH, 2.07 +/- 1.16; microsomal 3 beta-HSDH, 8.95 +/- 5.20. No dependence on sex or age was detected, but this may have been due to the heterogeneity of the sample material rather than a genuine absence of such correlations.
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific); D000293:Adolescent; D000328:Adult; D003593:Cytoplasm / Q000201:enzymology; D005260:Female; D006801:Humans; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology; D008875:Middle Aged
chemical_list: D015067:17-Hydroxysteroid Dehydrogenases; D015096:3-Hydroxysteroid Dehydrogenases; D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific)