Oral exposure to benzo[a]pyrene in the mouse: detoxication by inducible cytochrome P450 is more important than metabolic activation.

  title={Oral exposure to benzo[a]pyrene in the mouse: detoxication by inducible cytochrome P450 is more important than metabolic activation.},
  author={Shigeyuki Uno and Timothy P. Dalton and Sandrine Derkenne and Christine Perdan Curran and Marian L Miller and Howard G. Shertzer and Daniel W. Nebert},
  journal={Molecular pharmacology},
  volume={65 5},
The cytochrome P450 (CYP1A1) enzyme metabolically activates many polycyclic aromatic hydrocarbons, including benzo[a]pyrene (BaP), to DNA- and protein-binding intermediates that are associated with toxicity, mutagenesis, and carcinogenesis. As a result, it is widely accepted that CYP1A1 potentiates the toxicity of this class of chemicals. In distinct contrast, we show here that CYP1A1 inducibility is essential in the detoxication of oral BaP. We compared Cyp1a1(-/-) knockout mice, having the… 

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