Ethanol Induced Alteration of Microsomal Membrane Bound Enzymes of Rat Liver in Vitro

Abstract

A bstract: Ethanol appeared to inhibit more readily the 0-demethylation of p-nitroanisole than the activity of arylhydrocarbon hydroxylase. Arylhydrocarbon hydroxylase was more sensitive to the inhibition by ethanol in control or phenobarbital pretreated rats than in rats administered 3,4-benzpyrene. Ethanol was shown to activate the glucuronidation of p-nitrophenol at 2.45 mol/l, which was followed by inhibition at higher ethanol concentrations. A similar activation could also be demonstrated in rats pretreated with phenobarbital or 3,4-benzpyrene. This activation was not seen in microsomes pretreated in vitro with detergents like digitonin and cetylpyridinium chloride. Glucose 6-phosphatase was not clearly inhibited until the ethanol concentration was as high as 4 mol/l. Digitonin and trypsin treatments of the microsomal membrane in virro appeared to activate the measurable glucose 6-phosphatase activity.