title: Detection of oxygen radicals during reperfusion of intestinal cells in vitro.
abstract: The nitroxide OXANO. (2-Ethyl-2,5,5-trimethyl-3-oxazolidinoxyl) which in its reduced form, OXANOH (2-Ethyl-1-hydroxy-2,5,5-trimethyl-3-oxazolidine), is capable of reacting with short-lived radicals, forming a secondary stable radical, was used for ESR-detection of radical production in isolated cells. The properties of OXANO. and OXANOH in terms of stability in cellular and subcellular systems, membrane permeability and effects on cellular viability were evaluated. Ischemia and reperfusion was simulated in vitro in a preparation of cells from rat intestinal mucosa by incubation at high density (4 X 10(8) cells/ml) under an atmosphere of nitrogen for 25 min and resuspended with fresh oxygenated buffer containing 5 mM OXANOH. A significant increase in radical formation during the 15 min reperfusion period studied was obtained in cells exposed to ischemia compared to control cells incubated at normal density under an atmosphere of oxygen. The addition of 5 microM of the scavenging enzyme superoxide dismutase reduced the radical formation by 50%. The time sequence of the superoxide formation was calculated as the difference in radical production in the presence and absence of superoxide dismutase.
authors.affiliation: Department of Biochemistry and Biophysics, Chalmers University of Technology, Göteborg, Sweden.
authors.forename: U A
authors.initials: UA
authors.lastname: Nilsson
authors.forename: L I
authors.initials: LI
authors.lastname: Olsson
authors.forename: H
authors.initials: H
authors.lastname: Thor
authors.forename: P
authors.initials: P
authors.lastname: Moldeus
authors.forename: A C
authors.initials: AC
authors.lastname: Bylund-Fellenius
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004355:Drug Stability; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D005978:Glutathione / Q000378:metabolism; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000098:blood supply*; D007511:Ischemia / Q000378:metabolism*; D008297:Male; D008797:Metyrapone / Q000494:pharmacology; D008862:Microsomes, Liver / Q000378:metabolism; D009584:Nitrogen / Q000008:administration & dosage; D010080:Oxazoles / Q000378:metabolism / Q000494:pharmacology; D010084:Oxidation-Reduction; D010100:Oxygen / Q000008:administration & dosage; D051381:Rats; D011919:Rats, Inbred Strains; D013113:Spin Labels; D013482:Superoxide Dismutase / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism*
chemical_list: D005609:Free Radicals; D010080:Oxazoles; D013113:Spin Labels; D013481:Superoxides; C034590:2-ethyl-2,5,5-trimethyl-3-oxazolidinoxyl; D003577:Cytochrome P-450 Enzyme System; D013482:Superoxide Dismutase; D005978:Glutathione; D009584:Nitrogen; D010100:Oxygen; D008797:Metyrapone