Objective:To study the effect of reactive oxygen species of inducing apoptosis on the heptocacinoma tissues following ischemia and reperfusion and perfusion hyperoxia liquid of hepatocarcinoma. Methods: The hepatocarcinoma animal models ware established by implantation of VX2 tumor constitution mass into the left middle lobe of liver of rabbits. The animals were subjected to 60 min clamp-induced ischemia of hepatic artery distributing in the left middle lobe followed by reperfusion at 1 h

1 d

3 d and 7 d

respectively

and perfusion hyperoxia liquid （partial pressure of oxygen

PO2>80 kPa） at the same time with reperfusion beginning. The concentration of MDA and NO ware tested. Apoptotic changes in the hepatocarcinoma and normal hepatic tissues were observed by means of HE staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling （TUNEL）. Results:The concentration of MDA in normal hepatic tissues and hepatocarcinoma tissue increased followed ischemia and reperfusion especially for reperfusion 1 h （4.61±0.40

3.10±0.23） and restored to normal level at reperfusion 7 d in normal hepatic tissues but still kept high concentration in the hepatocarcinoma tissue. Even though concentration of MDA in normal hepatic tissues is higher than that of before ischemia and reperfusion

no difference have been found after perfusion of hyperoxia liquid

and in the hepatocarcinoma tissue

the increasing of concentration of MDA was obvious after simply ischemia and reperfusion at reperfusion 1 d （4.25±0.45）. The concentration of NO in normal hepatic tissues increased for reperfusion 3 d and 7 d（18.17±0.13

17.45±0.23）

while that of hepatocarcinoma tissue decreased at reperfusion 3 d（15.95±043）. After perfusion of hyperoxia liquid

the concentration of NO in normal hepatic tissues kept increasing and that decreased in the hepatocarcinoma tissues in all time point and reached the lowest level at reperfusion 1 d（14.62±0.45）.The result demonstrated the changes of concentration of NO and MDA in the hepatocarcinoma tissues ware more obvious than that of normal hepatic tissues（P<0.01）. Conclusion:Perfusion of hyperoxia liquid from hepatic portal vein can intensify ischemia and reperfusion injury but less so for normal hepatic tissues.