Cytochrome P-450 content and mixed-function oxidase activity in microsomes isolated from mouse skin

A microsomal fraction, prepared from mouse skin, catalyzed the hydroxylation of benzpyrene and aniline and the deethylation of 7-ethoxycoumarin. Contamination of the preparation by cytochrome oxidase and cytochrome P-420 was determined by spectral analysis. The enzyme activities studied in mouse ski...

Full description

Saved in:
Bibliographic Details
Published inDrug metabolism and disposition Vol. 4; no. 5; p. 442
Main Authors Pohl, R J, Philpot, R M, Fouts, J R
Format Journal Article
LanguageEnglish
Published United States 01.09.1976
Subjects
Aniline Hydroxylase - metabolism
Animals
Aryl Hydrocarbon Hydroxylases - metabolism
Carbon Monoxide - pharmacology
Coumarins
Cytochrome P-450 Enzyme System - analysis
Enzyme Induction - drug effects
Ethyl Ethers
Female
In Vitro Techniques
Male
Methylcholanthrene - pharmacology
Mice
Mice, Inbred Strains
Microsomes - enzymology
Microsomes, Liver - enzymology
Mixed Function Oxygenases - metabolism
NADPH-Ferrihemoprotein Reductase - metabolism
Oxidoreductases - metabolism
Polychlorinated Dibenzodioxins - pharmacology
Skin - enzymology
Skin - ultrastructure
Skin Absorption
Spectrophotometry
Online AccessGet more information

Cover

More Information
Summary:A microsomal fraction, prepared from mouse skin, catalyzed the hydroxylation of benzpyrene and aniline and the deethylation of 7-ethoxycoumarin. Contamination of the preparation by cytochrome oxidase and cytochrome P-420 was determined by spectral analysis. The enzyme activities studied in mouse skin (Swiss-Webster CD-1) did not respond to topical application of 3-MC. Twenty-four hours after topical application of TCDD to mice, microsomes from skin had 50% greater benzpyrene hydroxylase and 7-ethoxycoumarin deethylase activity, and 4- to 8-fold greater activity of these enzymes was seen after 72 hr. Increases in cytochrome P-450 content of skin microsomes could be demonstrated 24 and 72 hr after topical TCDD treatment of mice. Cholate treatment (solubilization) of skin microsomes, followed by centrifugation, removed the contaminating cytochrome oxidase. Quantitative and qualitative analyses of cytochrome P-450 difference spectra were made from the solubilized preparations.
ISSN:0090-9556