title: Nitric oxide averts hypoxia-induced damage during reoxygenation in rat heart.
abstract: Nitric oxide (NO), synthesized by the hemoproteins NO synthases (NOS), is known to play important roles in physiological and pathological conditions in the heart, including hypoxia/reoxygenation (H/R). This work investigates the role that endogenous NO plays in the cardiac H/R-induced injury. A follow-up study was conducted in Wistar rats subjected to 30 min of hypoxia, with or without prior treatment using the nonselective NOS inhibitor L-NAME (1.5 mM). The rats were studied at 0 h, 12 h, and 5 days of reoxygenation, analysing parameters of cell, and tissue damage (lipid peroxidation, apoptosis, and protein nitration), as well as in situ NOS activity and NO production (NOx). The results showed that after L-NAME administration, in situ NOS activity was almost completely eliminated in all the experimental groups, and consequently, NOx levels fell. Contrarily, the lipid peroxidation level and the percentage of apoptotic cells rose throughout the reoxygenation period. These results reveal that NOS inhibition exacerbates the peroxidative and apoptotic damage observed before the treatment with L-NAME in the hypoxic heart, pointing to a cardioprotective role of NOS-derived NO against H/R-induced injury. These findings could open the possibility of future studies to design new therapies for H/R-dysfunctions based on NO-pharmacology.
authors.affiliation: Department of Experimental Biology, University of Jaén, Paraje Las Lagunillas s/n, Jaén 23071, Spain. mrus@ujaen.es
authors.forename: Alma
authors.initials: A
authors.lastname: Rus
authors.forename: Francisco
authors.initials: F
authors.lastname: Molina
authors.forename: M Ángeles
authors.initials: MÁ
authors.lastname: Peinado
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Del Moral
mesh_terms: D000818:Animals; D017209:Apoptosis; D000860:Hypoxia / Q000150:complications*; D015227:Lipid Peroxidation; D008297:Male; D009206:Myocardium / Q000473:pathology*; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D015538:Nitrosation; D051381:Rats; D017208:Rats, Wistar
chemical_list: D009569:Nitric Oxide; D019001:Nitric Oxide Synthase