Increase of liver microsomal benzo(a)pyrene monooxygenase activity by subsequent glucuronidation
Benzo(a)pyrene monooxygenase activity in rat and guinea pig liver microsomes is markedly stimulated when UDP-glucuronic acid is present in the assay. This effect is further enhanced by addition of UDP-N-acetylglucosamine, an allosteric activator of UDP-glucuronyltransferase. The results suggest a coupling between microsomal monooxygenase and UDP-glucuronyltransferase which may assist elimination of toxic compounds.
Key wordsBenzo(a)pyrene monooxygenase UDP-glucuronyltransferase Enzyme coupling Enzyme induction Detoxication
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