Bile acids. XLVII. 12alpha-Hydroxylation of precursors of allo bile acids by rabbit liver microsomes.

TitleBile acids. XLVII. 12alpha-Hydroxylation of precursors of allo bile acids by rabbit liver microsomes.
Publication TypeJournal Article
Year of Publication1975
AuthorsAli SS, Elliott WH
JournalBiochim Biophys Acta
Volume409
Issue2
Pagination249-57
Date Published1975 Nov 21
ISSN0006-3002
KeywordsAging, Animals, Bile Acids and Salts, Female, Kinetics, Male, Microsomes, Liver, Mixed Function Oxygenases, NADP, Oxidation-Reduction, Rabbits, Sex Factors
Abstract

Rabbit liver microsomal preparations fortified with 0.1 mM NADPH effectively promote hydroxylation of [3beta-3H]- or [24-14C]allochenodeoxycholic acid or [5alpha,6alpha-3H2]5alpha-cholestane-3alpha,7alpha-diol to their respective 12alpha-hydroxyl derivatives in yields of about 25 or 65% in 60 min. Minor amounts of other products are formed from the diol. The requirements for activity of rabbit liver microsomal 12alpha-hydroxylase resemble those of rat liver microsomes. Of a number of enzyme inhibitors studied only p-chloromercuribenzoate demonstrated a marked ability to inhibit the reaction with either tritiated substrate. There was no difference in the quantity of product produced from the tritiated acid or the 14C-labeled acid. No clear sex difference was found in activity of the enzyme, nor was an appreciable difference noted in activity of the enzyme between mature and immature animals.

Alternate JournalBiochim. Biophys. Acta
PubMed ID65