ACETONE ENHANCEMENT OF MICROSOMAL ANILINE PARA-HYDROXYLASE ACTIVITY

Acetone in concentrations of 0.045-1.8 m markedly enhanced the para-hydroxylation of aniline by hepatic microsomal fractions derived from rats, mice, rabbits and dogs. Similarly acetone enhanced the hydroxylation of acetanilide and N-butylaniline but not the N-demethylation of ethylmorphine, N-methyl or N,N-dimethylaniline nor the O-demethylation of p-nitroanisole. The degree of enhancement increased with increasing pH. In the presence of acetone, both the Michaelis constant and maximal velocity for the hydroxylation of aniline increased. SKF 525-A and piperonyl butoxide were more potent inhibitors of aniline hydroxylation in the presence of acetone. Finally, evidence is presented that acetone produces its enhancement of aniline hydroxylation by a mechanism different from that of ethyl isocyanide. © 1968.