Cytochrome P450 1A2 (CYP1A2) (CYP1A2)

Cytochrome P450 1A2 (CYP1A2) is a critical hepatic enzyme within the CYP1 family responsible for the oxidative biotransformation of approximately 9% of clinically used drugs, including the isoquinoline alkaloid papaverine. Its primary biological function involves the O-demethylation and N-oxidation of planar aromatic compounds, converting them into more polar metabolites suitable for conjugation and renal excretion. In the case of papaverine, CYP1A2 facilitates its primary clearance pathway by converting it into various phenolic metabolites, such as 4'-desmethylpapaverine. Although papaverine acts pharmacologically as a non-selective phosphodiesterase (PDE) inhibitor to induce vasodilation, its therapeutic window and half-life are heavily influenced by the metabolic activity of CYP1A2. Variability in this enzyme's expression, due to genetic polymorphisms or environmental induction (e.g., tobacco smoke), can significantly alter drug exposure, potentially leading to subtherapeutic levels or toxic accumulation of substrates.

Other names

CYP1A2Cytochrome P450 Family 1 Subfamily A Member 2CP12P450(PA)P3-450Aryl hydrocarbon hydroxylase

Catalyzes the oxidative metabolism (specifically O-demethylation) of papaverine and other heterocyclic aromatic substrates.