Interindividual and interspecies variation in the metabolism of the hallucinogen 4-methoxyamphetamine.
1. The qualitative and quantitative aspects of the urinary elimination of orally administered 4-methoxy[14C]amphetamine have been examined in the rat and guinea-pig and in three volunteer human subjects, to determine interspecies and interindividual variations in disposition of the drug. 2. Both rat and guinea-pig excreted 70--80% of the administered dose(6 mg/kg) in the urine within 24 h, mainly as metabolites. 3. In the guinea-pig, the drug was metabolized by O-demethylation to give 4-hydroxyamphetamine, which was excreted free (4% dose) and conjugated (73%). No other metabolite was detected. 4. The rat metabolizes the drug both by O-dealkylation and by side-chain oxidation, the products being 4-hydroxyamphetamine (5% of dose free and 60% conjugated) and 1-(4'-methoxyphenyl)propan-2-one oxime (5% dose, free and conjugated). 5. In man the drug (dose 5 mg) is metabolized by O-demethylation and by side-chain oxidation. Marked intersubject variations were observed both in the array and quantitative aspects of metabolite excretion. Two subjects excreted mainly 4-hydroxyamphetamine (free and conjugated) together with smaller amounts of 1-(4'-methoxyphenyl)propan-2-one oxime and 4-hydroxynorephedrine. The third subject, however, who was previously known to exhibit a genetically determined defect in drug oxidation, was defective in O-dealkylation of 4-methoxyamphetamine, and the main excretion products were the unchanged drug together with products of side-chain oxidation, namely, 1-(4'-methoxyphenyl)propan-2-one oxime, 1-(4'-methoxyphenyl)propan-2-one and 4-methoxybenzoic acid. 6. Inter-individual differences in oxidative O-demethylation of the drug are discussed in relation to current theories on the aetiology of schizophrenia and reported fatalities arising from abuse of the drug.
D000328:Adult; D000662:Amphetamines / Q000031:analogs & derivatives / Q000378:metabolism* / Q000652:urine; D000818:Animals; D001565:Benzoates / Q000652:urine; D003640:Dealkylation; D003641:Deamination; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D062385:Hydroxybenzoates / Q000652:urine; D008297:Male; D010084:Oxidation-Reduction; D010091:Oximes / Q000652:urine; D010641:Phenotype; D051381:Rats; D013045:Species Specificity; D010136:p-Hydroxyamphetamine / Q000652:urine; D010137:p-Hydroxynorephedrine / Q000652:urine
D000662:Amphetamines; D001565:Benzoates; D062385:Hydroxybenzoates; D010091:Oximes; D010137:p-Hydroxynorephedrine; D010136:p-Hydroxyamphetamine