Microsome-dependent methylation of erythrocyte proteins by dimethylnitrosamine.
The precarcinogen, N-[methyl-14C]dimethylnitrosamine, rat liver microsomes and NADPH were incubated in the presence of intact human erythrocytes. Uptake of radioactivity into erythrocytes was time-dependent and analysis of an acid hydrolysate of the erythrocyte proteins showed several radioactive peaks which were identified as 3-N-methyl- and 1-N-methyl-histidine, S-methyl-cysteine. Since no binding occurs in the absence of microsomes, the alkylating species from dimethylnitrosamine metabolism can clearly penetrate the erythrocyte plasma membrane.
D000596:Amino Acids / Q000097:blood; D000818:Animals; D001798:Blood Proteins / Q000378:metabolism*; D004128:Dimethylnitrosamine / Q000097:blood / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008745:Methylation; D008862:Microsomes, Liver / Q000378:metabolism*; D051381:Rats
D000596:Amino Acids; D001798:Blood Proteins; D004128:Dimethylnitrosamine