Interactions of amphetamine analogs with human liver CYP2D6.

Article Details

Citation

Wu D, Otton SV, Inaba T, Kalow W, Sellers EM

Interactions of amphetamine analogs with human liver CYP2D6.

Biochem Pharmacol. 1997 Jun 1;53(11):1605-12.

PubMed ID
9264312 [ View in PubMed
]
Abstract

The interaction of fifteen amphetamine analogs with the genetically polymorphic enzyme CYP2D6 was examined. All fourteen phenylisopropylamines tested were competitive inhibitors of CYP2D6 in human liver microsomes. The presence of a methylenedioxy group in the 3,4-positions of both amphetamine (Ki = 26.5 microM) and methamphetamine (Ki = 25 microM) increased the affinity for CYP2D6 to 1.8 and 0.6 microM, respectively. Addition of a methoxy group to amphetamine in the 2-position also increased the affinity for CYP2D6 (Ki = 11.5 microM). The compound with the highest affinity for CYP2D6 was an amphetamine analog (MMDA-2) having both a methoxy group in the 2-position and a methylenedioxy group (Ki = 0.17 microM). Mescaline did not interact with CYP2D6. O-Demethylation of p-methoxyamphetamine (PMA) by CYP2D6 was characterized (Km = 59.2 +/- 22.4 microM, and Vmax = 29.3 +/- 16.6 nmol/mg/hr, N = 6 livers). This reaction was negligible in CYP2D6-deficient liver microsomes, was inhibited stereoselectively by the quinidine/quinine enantiomer pair, and was cosegregated with dextromethorphan O-demethylation (r = 0.975). The inhibitory effect of methylenedioxymethamphetamine (MDMA) was enhanced by preincubation with microsomes, suggesting that MDMA may produce a metabolite complex with CYP2D6. These findings suggest that phenylisopropylamines as a class interact with CYP2D6 as substrates and/or inhibitors. Their use may cause metabolic interactions with other drugs that are CYP2D6 substrates, and the potential for polymorphic oxidation via CYP2D6 may be a source of interindividual variation in their abuse liability and toxicity.

DrugBank Data that Cites this Article

Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
4-MethoxyamphetamineCytochrome P450 2D6ProteinHumans
Unknown
Substrate
Details
AmphetamineCytochrome P450 2D6ProteinHumans
Unknown
Substrate
Details