AIM To study the role of lipid peroxides reaction on hepatic ischemia damage and the protective effects ofantioxidants (TMP, co-Q10).MgTHODS Twenty-four adult dogs were performed portacaval shunt and randomly put into 3 groups:group 1 (control group); 8 dogs with portacaval shunt (PCS group); group 2:8 dogs with portacaval shuntand only given antioxidants -TMP (ligustrazine) (PCS + TMP group); group 3:8 dogs with portacaval shuntand given antioxidants in combination with co-Q10, TMP and co-Q10 (PCS + TMP + co-Q10 group). Drugusage: TMP, 50 mg/ kg/ isolation day; coenzyme Q10, 1.5 mg/kg/isolation day; PCS + TMP, given up atthe end of 4 weeks after operation; and PCS + TMP + co-Q10, given up at the end of 8 weeks afteroperation. The experiment indices: super-peroxide dismutase (SOD), malondialdehyde (MDA), ALT,AST, AKP were all measured before operation, and 8 weeks after operation. The liver tissues were obtainedin the 4th week and 8th week respectively after operation and the changes of hepatic structures were observedunder light and electronic microscope.RESULTS There were obvious increase of MDA and decrease of SOD in PCS group, which was remarkablydifferent from pre-operation (P0.05). But it was remarkably different from PCS group(P0.05).In PCS+ TMP+ co-QlO group, MDA increased slightlly, and SOD decreated, but it was superior to that inPCS and PCS + TMP groups. The data in PCS + TMP + co-Q10 group had statistical significance compared tothat in PCS+ TMP group (P