Crossref journal-article
Portland Press Ltd.
Biochemical Journal (288)
Abstract

In order to distinguish between the mechanism of microsomal ethanol oxidation and hydroxyl-radical formation, the rate of cytochrome P-450 (P-450)-dependent oxidation of dimethyl sulphoxide (Me2SO) was determined in the presence and in the absence of iron-chelating compounds, in liver microsomes from control, ethanol- and phenobarbital-treated rats. Ethanol treatment resulted in a specific increase (3-fold) of the microsomal ethanol oxidation and NADPH consumption per nmol of P-450. A form of P-450 was purified to apparent homogeneity from the ethanol-treated rats and characterized with respect of amino acid composition and N-terminal amino acid sequence. Specific ethanol induction of a cytochrome P-450 species having a catalytic-centre activity of 20/min for ethanol and consuming 30 nmol of NADPH/min could account for the results observed with microsomes. Phenobarbital treatment caused 50% decrease in the rate of ethanol oxidation and NADPH oxidation per nmol of P-450. The rate of oxidation of the hydroxyl-radical scavenger Me2SO was increased 3-fold by ethanol or phenobarbital treatment when expressed on a per-mg-of-microsomal-protein basis, but the rate of Me2SO oxidation expressed on a per-nmol-of-P-450 basis was unchanged. Addition of iron-chelating agents to the three different types of microsomal preparations caused an ‘uncoupling’ of the electron-transport chain accompanied by a 4-fold increase of the rate of Me2SO oxidation. It is concluded that ethanol treatment results in the induction of P-450 forms specifically effective in ethanol oxidation and NADPH oxidation, but not in hydroxyl-radical production, as detected by the oxidation of Me2SO.

Bibliography

Ekström, G., Cronholm, T., & Ingelman-Sundberg, M. (1986). Hydroxyl-radical production and ethanol oxidation by liver microsomes isolated from ethanol-treated rats. Biochemical Journal, 233(3), 755–761.

Authors 3
  1. G Ekström (first)
  2. T Cronholm (additional)
  3. M Ingelman-Sundberg (additional)
References 0 Referenced 70

None

Dates
Type When
Created 10 years ago (Aug. 10, 2015, 4:52 p.m.)
Deposited 3 years, 9 months ago (Nov. 25, 2021, 11:26 a.m.)
Indexed 1 year ago (Aug. 5, 2024, 6:39 p.m.)
Issued 39 years, 6 months ago (Feb. 1, 1986)
Published 39 years, 6 months ago (Feb. 1, 1986)
Published Print 39 years, 6 months ago (Feb. 1, 1986)
Funders 0

None

@article{Ekstr_m_1986, title={Hydroxyl-radical production and ethanol oxidation by liver microsomes isolated from ethanol-treated rats}, volume={233}, ISSN={1470-8728}, url={http://dx.doi.org/10.1042/bj2330755}, DOI={10.1042/bj2330755}, number={3}, journal={Biochemical Journal}, publisher={Portland Press Ltd.}, author={Ekström, G and Cronholm, T and Ingelman-Sundberg, M}, year={1986}, month=feb, pages={755–761} }