Hepatic microsomal enzyme induction and urinary D-glucaric acid excretion in man

ABSTRACT

Liver biopsy material of six patients with Hodgkin's disease were used as controls for measurement of drug-metabolizing enzymes. Two patients were treated with 90mg of phenobarbitone to induce the hepatic enzymes and the excretion of D-glucaric acid in urine. The two phenobarbitone-treated patients showed increased activities of hexobarbitone oxidase, cytochrome P-450 and increased microsomal protein content. There was no change in the activities of ethylmorphine-N-demethylase, 1-leucyl-beta-naphthylamide splitting enzyme and UDP-glucuronyle transferase, while p-nitroreductase was repressed. The urinary excretion of D-glucaric acid was increased 2- and 20-fold in the two patients after treatment with phenobarbitone. It is not possible to draw any conclusions from the results regarding the relationship between the in vitro hepatic enzyme activities and the in vivo excretion of D-glucaric acid in the urine due to the small number of cases studied. However the limited observations suggest some interesting possibilities