title: Spin trapping of free radicals formed during peroxidation of sarcolemmal membranes (SLM).
abstract: The generation of free radicals in a superoxide (O2-.) driven Fe+3 catalysed reactions with isolated myocytic sarcolemma using electron spin resonance was investigated. Incubation of highly purified canine myocytic sarcolemma in the presence of the spin trap, 2-methyl-2-nitrosopropane (MNP), followed by the addition of dihydroxyfurmarate (DHF) and Fe+3-ADP resulted in the generation and detection of radical adducts of this spin trap. Spin trapping of the alkyl radicals with 2-methyl-2-nitrosopropane led to the identification of methyl radical adduct following exposure to DHF/Fe+3-ADP. With sarcolemma and the alkyl nitroso compound, the only radical product trapped was the methyl radical formed by beta-scission of alkoxyl radical. The participation of hydroperoxide-derived radicals in this system verified that the decomposition of unsaturated hydroperoxy fatty acid does proceed via a free radical mechanism.
authors.affiliation: Department of Medicine, George Washington University Medical Center, Washington, DC 20037.
authors.forename: C M
authors.initials: CM
authors.lastname: Arroyo
authors.forename: I T
authors.initials: IT
authors.lastname: Mak
authors.forename: W B
authors.initials: WB
authors.lastname: Weglicki
mesh_terms: D000818:Animals; D004285:Dogs; D004578:Electron Spin Resonance Spectroscopy; D005290:Ferric Compounds; D005609:Free Radicals; D008054:Lipid Peroxides; D009206:Myocardium; D010084:Oxidation-Reduction; D012508:Sarcolemma; D013481:Superoxides
chemical_list: D005290:Ferric Compounds; D005609:Free Radicals; D008054:Lipid Peroxides; D013481:Superoxides