THE INVOLVEMENT OF CYP3A4 AND CYP2C9 IN THE METABOLISM OF 17α-ETHINYLESTRADIOL

@article{Wang2004THEIO,
  title={THE INVOLVEMENT OF CYP3A4 AND CYP2C9 IN THE METABOLISM OF 17$\alpha$-ETHINYLESTRADIOL},
  author={Bonnie Wang and Rosa I. Sanchez and Ronald B. Franklin and D. C. Evans and S W Huskey},
  journal={Drug Metabolism and Disposition},
  year={2004},
  volume={32},
  pages={1209 - 1212}
}
The role of specific cytochrome P450 (P450) isoforms in the metabolism of ethinylestradiol (EE) was evaluated. The recombinant human P450 isozymes CYP1A1, CYP1A2, CYP2C9, CYP2C19, and CYP3A4 were found to be capable of catalyzing the metabolism of EE (1 μM). Without exception, the major metabolite was 2-hydroxy-EE. The highest catalytic efficiency (Vmax/Km) was observed with rCYP1A1, followed by rCYP3A4, rCYP2C9, and rCYP1A2. The P450 isoforms 3A4 and 2C9 were shown to play a significant role… Expand

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