(2)mechanism of increase of oxygen free radical O formation of oxygen free radical nature oxidation of Hb, Cwt C 0,-0,=0,=OH=,O HO oxidation of enzyme: xanthine oxidase(XO) xanthine uric acid OO Mitochondria: o(2) mechanism of increase of oxygen free radical ① formation of oxygen free radical nature oxidation of Hb , Cyt C O2 O ‾∙ 2 H2O2 OH∙ H2O H2O oxidation of enzyme : xanthine oxidase(XO) O ‾∙ 2 xanthine uric acid O2 O ‾∙ 2 Mitochondria: O ‾∙ 2