Quinine is a more potent inhibitor than quinidine in rat of the oxidative metabolic routes of methoxyphenamine which involve debrisoquine 4-hydroxylase.

@article{Muralidharan1991QuinineIA,
  title={Quinine is a more potent inhibitor than quinidine in rat of the oxidative metabolic routes of methoxyphenamine which involve debrisoquine 4-hydroxylase.},
  author={G. Muralidharan and Edward M. Hawes and Gordon Mckay and Kamal K. Midha},
  journal={Xenobiotica; the fate of foreign compounds in biological systems},
  year={1991},
  volume={21 11},
  pages={
          1441-50
        }
}
  • G. Muralidharan, E. Hawes, K. Midha
  • Published 1 November 1991
  • Chemistry, Biology, Medicine
  • Xenobiotica; the fate of foreign compounds in biological systems
1. Lewis rats (n = 7 or 8) were dosed with methoxyphenamine with and without prior administration of various doses of either quinine or its diastereomer quinidine. Methoxyphenamine and its N-desmethyl, O-desmethyl and aromatic 5-hydroxy metabolites were quantified in 0-24 h urine. 2. The oxidative routes of methoxyphenamine metabolism which had been previously shown to involve the debrisoquine/sparteine isoenzyme, namely O-demethylation and 5-hydroxylation, were both significantly inhibited by… 
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TLDR
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TLDR
A protocol involving substrate administration to Lewis strain rats with and without prior administration of quinidine could be developed as an attractive approach to screen substrates for metabolism in vivo by the debrisoquine/sparteine isozyme.
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Both quinidine and quinine decreased the excretion of 2‐OH‐DMI, virtually transforming rapid hydroxylators into slow hydroxyators and a stereoselective inhibition of DMI 2‐hydroxylation.
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TLDR
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TLDR
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TLDR
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