title: Leukotriene B4, C4, D4 and E4 inactivation by hydroxyl radicals.
abstract: Leukotriene B4 chemotactic activity and leukotriene C4, D4 and E4 slow reacting substance activity were rapidly decreased by hydroxyl radicals generated by two different iron-supplemented acetaldehyde-xanthine oxidase systems. At low Fe2+, leukotriene inactivation was inhibited by catalase, superoxide dismutase, mannitol and ethanol, suggesting involvement of hydroxyl radicals generated by the iron-catalyzed interaction of superoxide and H2O2 (Haber-Weiss reaction). Leukotriene inactivation increased at high Fe2+ concentrations, but was no longer inhibitable by superoxide dismutase, suggesting that inactivation resulted from a direct interaction between H2O2 and Fe2+ to form hydroxyl radicals (Fenton reaction). The inactivation of leukotrienes by hydroxyl radicals suggests that oxygen metabolites generated by phagocytes may play a role in modulating leukotriene activity.
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D005609:Free Radicals; D006878:Hydroxides / Q000378:metabolism*; D017665:Hydroxyl Radical; D007700:Kinetics; D007975:Leukotriene B4 / Q000378:metabolism*; D017999:Leukotriene E4; D008892:Milk / Q000201:enzymology; D013189:SRS-A / Q000031:analogs & derivatives* / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014969:Xanthine Oxidase / Q000378:metabolism
chemical_list: D005609:Free Radicals; D006878:Hydroxides; D013189:SRS-A; D007975:Leukotriene B4; D017665:Hydroxyl Radical; D017999:Leukotriene E4; D014969:Xanthine Oxidase