• Corpus ID: 33852376

Use of quinidine inhibition to define the role of the sparteine/debrisoquine cytochrome P450 in metoprolol oxidation by human liver microsomes.

  title={Use of quinidine inhibition to define the role of the sparteine/debrisoquine cytochrome P450 in metoprolol oxidation by human liver microsomes.},
  author={S. Victoria Otton and H. Kim Crewe and Martin S. Lennard and Geoffrey T Tucker and H. F. Woods},
  journal={The Journal of pharmacology and experimental therapeutics},
  volume={247 1},
  • S. OttonH. Crewe H. Woods
  • Published 1 October 1988
  • Biology, Chemistry
  • The Journal of pharmacology and experimental therapeutics
The oxidation of the beta adrenoceptor antagonist metoprolol exhibits genetic polymorphism of the sparteine/debrisoquine (SP/DB) type. The alpha-hydroxylation of metoprolol is absent in poor metabolizers, whereas metoprolol O-demethylation is only partially impaired, suggesting that an enzyme or enzymes other than cytochrome P450-SP/DB contribute to the latter reaction. Using inhibition by the quinidine/quinine isomer pair as a marker for the activity of cytochrome P450-SP/DB, the role of this… 

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