title: Organ-specific properties of cytochromes P-450s21 (steroid 21-hydroxylases) of liver and adrenocortical microsomes.
abstract: Organ specificities of cytochrome P-450s21 (steroid 21-hydroxylase) were investigated. The substrate specificity of the liver cytochrome P-450s21 was found to be different from that of adrenocortical cytochrome P-450s21. The steroid 21-hydroxylase activity of liver microsomes decreased with treatment by sodium phenobarbital or beta-naphthoflavone and was inhibited by anti-cytochrome b5 immunoglobulin, although that of adrenocortical microsomes was not. The liver cytochrome P-450s21 was immunochemically similar to adrenocortical cytochrome P-450s21. The bovine liver and adrenocortical cytochromes P-450s21 showed immunoprecipitin lines against antibody to bovine adrenocortical cytochrome P-450s21. The molecular masses of the bovine liver and adrenocortical cytochromes P-450s21 were 60 +/- 1 and 50 +/- 1 kDa, respectively. The content of cytochrome P-450s21 and its percentage for the total microsomal cytochrome P-450 were immunochemically determined using the antibody to the bovine adrenocortical cytochrome P-450s21.
mesh_terms: D000302:Adrenal Cortex / Q000201:enzymology*; D000818:Animals; D002417:Cattle; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D005779:Immunodiffusion; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D008861:Microsomes / Q000201:enzymology; D008862:Microsomes, Liver / Q000201:enzymology*; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D013255:Steroid 21-Hydroxylase / Q000378:metabolism; D013379:Substrate Specificity; D014018:Tissue Distribution
chemical_list: D007527:Isoenzymes; D003577:Cytochrome P-450 Enzyme System; D013255:Steroid 21-Hydroxylase