title: N-acetylcysteine treatment prevents the up-regulation of MnSOD in chronically hypoxic rat hearts.
abstract: Chronic intermittent hypoxia (CIH) is associated with increased production of reactive oxygen species that contributes to the adaptive mechanism underlying the improved myocardial ischemic tolerance. The aim was to find out whether the antioxidative enzyme manganese superoxide dismutase (MnSOD) can play a role in CIH-induced cardioprotection. Adult male Wistar rats were exposed to intermittent hypobaric hypoxia (7000 m, 8 h/day, 25 exposures) (n=14) or kept at normoxia (n=14). Half of the animals from each group received N-acetylcysteine (NAC, 100 mg/kg) daily before the hypoxic exposure. The activity and expression of MnSOD were increased by 66 % and 23 %, respectively, in the mitochondrial fraction of CIH hearts as compared with the normoxic group; these effects were suppressed by NAC treatment. The negative correlation between MnSOD activity and myocardial infarct size suggests that MnSOD can contribute to the improved ischemic tolerance of CIH hearts.
authors.affiliation: Department of Cell Biology, Charles University, Faculty of Science, Prague, Czech Republic.
authors.forename: P
authors.initials: P
authors.lastname: Balková
authors.forename: M
authors.initials: M
authors.lastname: Hlaváčková
authors.forename: M
authors.initials: M
authors.lastname: Milerová
authors.forename: J
authors.initials: J
authors.lastname: Neckář
authors.forename: F
authors.initials: F
authors.lastname: Kolář
authors.forename: F
authors.initials: F
authors.lastname: Novák
authors.forename: O
authors.initials: O
authors.lastname: Nováková
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D016166:Free Radical Scavengers / Q000494:pharmacology* / Q000627:therapeutic use; D000860:Hypoxia; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000517:prevention & control*; D009206:Myocardium / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D013482:Superoxide Dismutase; D000111:Acetylcysteine