Objective:To evaluate the action of arsenic trioxide(As 2O 3)on mitochondria of hepatic Vx-2 carcinoma by transcatheter arterial infusion(TAI).Methods:Fifty New Zealand rabbits weighing 2-3kg with hepatic Vx-2 carcinoma were randomly divided into five groups evenly.Two weeks after the tumor was implanted

the rabbits were treated with As 2O 3 (experimental groups)

cisplatin or normal saline(control groups)by TAI for 7 days consecutively.Three weeks after drug administration

the mitochondrial morphological changes and mitochondrial specific surface areas of the tumor and hepatic tissues were investigated under transmission elcetron microscope

at the same time apoptosis of the tumor was observed.Results:The mitochondrial morphological changes of tumor were obvious in the experimential groups as compared with control groups( P <0.01).The mitochondrial specific surface area of tumor cells was significantly different among the experimental groups and control groups( P <0.05).They were also significantly different among experimental groups or between tumor cells and hepatic cells in the same experimental groups( P <0.05).Mitochondria changes of the tumor was consistent with the generation of its apoptosis.Conclusion:The results show that As 2O 3 by TAI can damage the mitochondria of tumor cells selectively

and the effect is dose dependent.