J. Schenkman, J. Ball, R. Estabrook
Jun 1, 1967
Citations
1
Influential Citations
87
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Quality indicators
Journal
Biochemical pharmacology
Abstract
Abstract Nicotinamide, an additive to almost all media used to study oxidative metabolism of substrates of hepatic microsomal mixed-function oxidase, is shown to inhibit the metabolism of known substrates of this system. Inhibition of aminopyrine demethylation appears to be competitive, while inhibition of aniline hydroxylation appears to be a mixture of competitive and noncompetitive inhibition. It is shown that an accurate assay of substrate metabolism can be obtained in the absence of nicotinamide if the assay time is kept short, NADPH concentration is maintained at a high level, and the concentration of microsomes in the medium is kept low.