Specificity of amine oxidase for optically active substrates and inhibitors.

A number of optically active amines have been tested as substrates or inhibitors of amine oxidase of rabbit and guinea-pig liver. The two stereoisomers of beta-hydroxyphenethylamine were oxidized at the same rate by rabbit liver, but the guinea-pig liver extracts oxidized the D form more rapidly than the L form. The two stereoisomers of amphetamine were equally active as inhibitors of the rabbit liver oxidase, but with guinea-pig liver extracts dexamphetamine, the (+) form, was more potent as an inhibitor. In both species, 2-hydroxy-1-phenylethylamine was a weaker inhibitor than 1-phenylethylamine; in the rabbit liver (+) forms of these two amines were more potent as inhibitors.