Metabolism of Drugs. L II.Enzymatic Study on Secobarbital Metabolism

Abstract

[omega] and ([omega]-1)-Oxidation of secobarbital was studied with cell free systems of rabbit liver. By gas chromatography, secobarbital was found to be metabolized into ([omega]-1)-hydroxysecobarbital, [omega]-carboxysecobarbital, and ([omega]-1)-oxo-secobarbital by incubation with 9000 g supernatant fraction of liver homogenate. When secobarbital was incubated with microsomes with addition of NADPH and oxygen, formation of ([omega]-1)-hydroxysecobarbital was detected, but not that of [omega]-hydroxysecobarbital. Oxidation of [omega]-hydroxysecobarbital and ([omega]-1)-hydroxysecobarbital with the soluble fraction was demonstrated. Neither horse liver alcohol dehydrogenase nor 3-hydroxymethylhexabarbital dehydrogenase was concerned with the metabolism of secobarbital in rabbit liver.