Human Cytochrome P450: Metabolism of Testosterone by CYP3A4 and Inhibition by Ketoconazole
Open Access
- 1 May 2004
- journal article
- unit
- Published by Wiley in Current Protocols in Toxicology
- Vol. 20 (1), 4.13.1-4.13.9
- https://doi.org/10.1002/0471140856.tx0413s20
Abstract
This unit describes methods for measuring CYP3A4 activity using testosterone as a specific substrate, and for measuring CYP3A4 inhibition using ketoconazole as a selective inhibitor of testosterone oxidation. CYP3A4 is one of the most important and most abundant drug‐metabolizing CYP isoforms in human liver microsomes (∼40% of total CYP), and it has the broadest substrate specificity. It is important to determine whether CYP3A4 is involved in its metabolism.Keywords
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