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Exogenous reactive oxygen species deplete the isolated rat heart of antioxidants
- Source :
- Free radical biologymedicine. 22(1-2)
- Publication Year :
- 1997
-
Abstract
- The effects of reactive oxygen species (ROS) on myocardial antioxidants and on the activity of oxidative mitochondrial enzymes were investigated in the following groups of isolated, perfused rat hearts. I: After stabilization the hearts freeze clamped in liquid nitrogen ( n = 7). II: Hearts frozen after stabilization and perfusion for 10 min with xanthine oxidase (XO) (25 U/l) and hypoxanthine (HX) (1 mM) as a ROS-producing system ( n = 7). III: Like group II, but recovered for 30 min after perfusion with XO + HX ( n = 9). IV: The hearts were perfused and freeze-clamped as in group III, but without XO + HX ( n = 7). XO + HX reduced left ventricular developed pressure and coronary flow to approximately 50% of the baseline value. Myocardial content of hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) increased at the end of XO + HX perfusion, indicating that generation of ROS and lipid peroxidation occurred. Levels of H 2 O 2 and MDA normalized during recovery. Superoxide dismutase, reduced glutathione and α -tocopherol were all reduced after ROS-induced injury. ROS did not significantly influence the tissue content of coenzyme Q 10 (neither total, oxidized, nor reduced), cytochrome c oxidase, and succinate cytochrome c reductase. The present findings indicate that the reduced contractile function was not correlated to reduced activity of the mitochondrial electron transport chain. ROS depleted the myocardium of antioxidants, leaving the heart more sensitive to the action of oxidative injury. Copyright © 1996 Elsevier Science Inc.
- Subjects :
- Male
Xanthine Oxidase
Oxidative phosphorylation
In Vitro Techniques
Biochemistry
Antioxidants
Mitochondria, Heart
Statistics, Nonparametric
Lipid peroxidation
Superoxide dismutase
Electron Transport
chemistry.chemical_compound
Physiology (medical)
Coronary Circulation
Ventricular Pressure
Cytochrome c oxidase
Animals
Rats, Wistar
Xanthine oxidase
chemistry.chemical_classification
Reactive oxygen species
Hypoxanthine
biology
Myocardium
Malondialdehyde
Molecular biology
Glutathione
Myocardial Contraction
Rats
Perfusion
chemistry
Coenzyme Q – cytochrome c reductase
biology.protein
Reactive Oxygen Species
Subjects
Details
- ISSN :
- 08915849
- Volume :
- 22
- Issue :
- 1-2
- Database :
- OpenAIRE
- Journal :
- Free radical biologymedicine
- Accession number :
- edsair.doi.dedup.....44ed5af3947935ef0cee6a3473ba43f0