Metabolism of 32-oxo-24,25-dihydrolanosterols by partially purified cytochrome P-45014DM from rat liver microsomes.

Publisher Website
Google Scholar
Abstract
Metabolism of 32-oxo-24,25-dihydrolanosterols (3.beta.-hydroxylanost-8-en-32-al (4, .DELTA.8-CHO) and 3.beta.-hydroxylanost-7-en-32-al (5, .DELTA.7-CHO)) was studied in a reconstituted system consisting of rat liver partially purified cytochrome P-450, which catalyzes lanosterol 14-demethylation (P-45014DM), and reduced nicotineamide adenine dinucleotide phosphate (NADPH)-cytochrome P-450 reductase. The reconstituted system converted .DELTA.8-CHO (4) to 4,4-dimethyl-5.alpha.-cholesta-8,14-dien-3.beta.-ol (2, 8, 14-Diene), which corresponds to the 14-deformylated product, .DELTA.7-CHO (5), the isomer of .DELTA.8-CHO (4), was not converted to the corresponding 14-deformylated product. The apparent Km value of cytochrome P-45014DM for .DELTA.8-CHO (4) was about 1/20 of that for 24,25-dihydrolanosterol (1, DHL). The metabolism of .DELTA.8-CHO (4) was inhibited by 7-oxo-24,25-dihydrolanosterol (6,7-oxo-DHL), which is a potent inhibitor of cholesterol biosynthesis from lanosterol or DHL (1). However, the metabolism of .DELTA.8-CHO (4) was less inhibited by 7-oxo-DHL (6) than that of DHL (1).

This publication has 13 references indexed in Scilit: