Objective   To study the DNA damage of benzoapyrene on mice br ain t issue.

  Methods   50 mice were divided into 5 groups randomly, there were 10 animals in each g roup:1control group; ovehicle group; low dose BaP group; ¼ medium dose BaP group; ½ high dose BaP group.The mice of low, medium and high dose BaP groups were administrated by intraperitoneal injection wit h BaP dissolved in vegetable oil at 1.3mg/kg, 3.2mg/kg and 7.8 mg/kg once, 4 times per week specially, the vehicle control group were given vegetable oil parallel and the control group were not given additional treatment.Some tox icological symptomes were observed during the experiments.After 10 weeks expose the mice were killed, the brains were removed.The DNA damage of t he mice brain tissues were detected by the methods of TdT-mediated xdUT P nick end Lableing(TU NEL)and Single Cell Glue Electrophor esis(SCGE).

  Results   1There were some neuro-toxic symptoms had been observed in BaP exposed mice, especial in the high-dose BaP group.oBy the method of TUEL, there were very significant differences of the damage rates between administrated g roups and control groups; there w er e very significant differences of the damag e rates among the low, medium and high dose BaP administrated groups(P < 10 ^-16~10 ^-62).By the method of SCGE, there were significant differences of DNA damage betw een the high dose BaP administrated group and the control groups(P < 0.05).

  Conclusion   Administration of BaP could damageneuron DNA of the mice brain, the high the BaP administration doses were, the high the damage rates were and the serious the DNA damage was.