Interactions of bupranolol with the polymorphic debrisoquine/sparteine monooxygenase (CYP2D6)

  title={Interactions of bupranolol with the polymorphic debrisoquine/sparteine monooxygenase (CYP2D6)},
  author={Josie Pressacco and R. Muller and Werner Kalow},
  journal={European Journal of Clinical Pharmacology},
SummaryThe β-adrenoceptor blocker bupranolol turned out to be a competitive inhibitor of the polymorphic cytochrome P450 CYP2D6 of which sparteine is a substrate. There was stereo-selectivity of bupranolol involved: (−)-bupranolol was the weakest inhibitor with an apparent Ki value of 1.32 μM, (+)-bupranolol was the most potent with an apparent Ki value of 0.55 μM, while the therapeutically used racemic bupranolol had an intermediate value of 0.88 μM. A 10 min pre-incubation of 5 μM bupranolol… 
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