N-Demethylation Reactions in Intact Erythrocytes and Erythrocyte Supernatant

While it is generally accepted that the liver is the primary organ of xenobiotic metabolism, it is also known that other tissues can contribute both to the activating and inactivating reactions. Recently mutagenicity tests using erythrocytes indicated that the latter can mediate in metabolic activation of premutagens (Norppa et al 1984). However, biochemical evidence is still scarce although hemoglobin can catalyze the hydroxylation of aniline (Mieyal et al 1976) and red blood cells seem to have intracellular enzymic systems similar to those of the microsome with regard to the NADH- and NADPH-dependant reductases and cytochrome b5 (Kuma et al 1976). This paper describes the N-demethylation of methylaniline in rat erythrocytes in different media and the effects of potential inhibitors in the rate of metabolite formation.