Title: | Inhibitory effect of some imidazole antifungal compounds on the synthesis of 16-ene-C19-steroid catalyzed by pig testicular microsomes |
Author(s): | Nakajin S; Takahashi K; Shinoda M; |
Address: | "Department of Biochemistry, Faculty of Pharmaceutical Sciences, Hoshi University, Tokyo, Japan" |
Journal Title: | J Steroid Biochem Mol Biol |
DOI: | 10.1016/0960-0760(91)90407-v |
ISSN/ISBN: | 0960-0760 (Print) 0960-0760 (Linking) |
Abstract: | "The activity of the enzyme (16-ene-C19-steroid synthesizing enzyme) responsible for the conversion of C21-steroids to 16-ene-C19-steroids, which was localized on pig testicular microsomes, was inhibited by some typical imidazole antifungal compounds such as clotrimazole, econazole, miconazole and ketoconazole which are known to be universal inhibitors of cytochrome P-450-dependent enzymes. The 50% inhibitory concentrations of clotrimazole, econazole and miconazole were 0.29, 0.36 and 1.25 microM, respectively for 16-ene-C19-steroid synthesizing enzyme activity. Clotrimazole was the most powerful inhibitor of all the compounds examined, which shows the competitive inhibition for 16-ene-C19-steroid synthesizing enzyme activity. The Ki-value was 0.26 microM for its activity. The degree of the inhibition by these imidazole compounds was very similar to the inhibition of 17 alpha-hydroxylase and C17,20-lyase activities on pig testicular microsomes" |
Keywords: | Aldehyde-Lyases/metabolism Androgens/*biosynthesis Androstadienes/*metabolism Androstenols/*metabolism Animals Antifungal Agents/*pharmacology *Cytochrome P-450 Enzyme Inhibitors Cytochrome P-450 Enzyme System/metabolism Imidazoles/*pharmacology Male Micr; |
Notes: | "MedlineNakajin, S Takahashi, K Shinoda, M eng England 1991/01/01 J Steroid Biochem Mol Biol. 1991 Jan; 38(1):95-9. doi: 10.1016/0960-0760(91)90407-v" |