A: Representative negative ion mode spectra; B: Representative tandem mass spectra. IR, ischemia-reperfusion; GW, animals treated with GW 4869; DMSO, group treated with dimethyl sulfoxide. AA, Arachidonic acid; EPA, Eicosapentaenoic acid; DHA, Docosahexaenoic acid; DGLA, Dihomo-gamma-linolenic acid.