Identification of Cytochrome P450 Isoforms Involved in the Metabolism of Paroxetine and Estimation of Their Importance for Human Paroxetine Metabolism Using a Population-Based Simulator

@article{Jornil2010IdentificationOC,
  title={Identification of Cytochrome P450 Isoforms Involved in the Metabolism of Paroxetine and Estimation of Their Importance for Human Paroxetine Metabolism Using a Population-Based Simulator},
  author={Jakob R Jornil and Klaus Gjervig Jensen and Frank Larsen and Kristian Linnet},
  journal={Drug Metabolism and Disposition},
  year={2010},
  volume={38},
  pages={376 - 385}
}
We identify here for the first time the low-affinity cytochrome P450 (P450) isoforms that metabolize paroxetine, using cDNA-expressed human P450s measuring substrate depletion and paroxetine-catechol (product) formation by liquid chromatography-tandem mass spectrometry. CYP1A2, CYP2C19, CYP2D6, CYP3A4, and CYP3A5 were identified as paroxetine-catechol-forming P450 isoforms, and CYP2C19 and CYP2D6 were identified as metabolizing P450 isoforms by substrate depletion. Michaelis-Menten constants Km… 

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