Inhibition of rat liver mitochondrial monoamine oxidase by chloramphenicol and 2-amino-1-p-nitrophenylpropane-1,3-diol.

Inhibition of rat liver mitochondrial monoamine oxidase by chloramphenicol and its hydrolytic product, 2-amino-1-p-nitrophenylpropane-1,3-diol, was studied. The enzyme activity and its inhibition by these two compounds were optimum at pH 7.0 after preincubation for 60 min, the time needed for maximum enzyme--inhibitor complex formation. Enzyme activity could be restored after prolonged dialysis. Monamine oxidase inhibition by chloramphenicol and its hydrolytic product was noncompetitive and reversible. Deamination of various monamines was not to the same degree by these compounds. Of the different antimicrobials studied, only chloramphenicol and its hydrolytic produced has a strong inhibitory effect on monoamine oxidase.