A comparative study of the effects of cadmium on microsomal mixed-function oxidase activities between kidney cortex and liver

Abstract

The effects of cadmium and phenobarbital (PB) administration on the activities of microsomal mixed-function oxidase (MFO) in rat kidney cortex and liver were studied. Five indices, including cytochrome P-450 contents, aniline hydroxylase, NADPH-cytochrome c reductase, amino-pyrine N-demethylase and 7-ethoxycoumarin O-deethylase activities, were assayed. By comparison, it was found that PB could induce MFO activities in kidney cortex microsomes and liver microsomes, both hepatic and renal microsomal MFO were decreased by the ip injection of CdCl₂, and Cd²⁺ could markedly decrease the phenobarbital induction to hepatic and renal microsomal MFO activities with the exception of NADPH-cytochrome c reductase in kidney cortex microsomes.

Keywords

cadmium / phenobarbital / kidney cortex microsomes / liver microsomes / microsomal drug-metabolising enzymes

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