[Establishment of mouse lung cancer model induced by benzo[a]pyrene dynamic inhalation exposure]

Objective: To establish a mouse lung cancer model induced by benzo[a]pyrene(B[a]P) dynamic inhalation exposure.

Methods: A total of 96 C57 BL/6 J mice weighing 18 to 20 g were randomly divided into the control group(n=48)and the experimental group(n=48), male and female in half. The experimental group was treated with 10. 0 μg/m~3 BaP for 13 weeks or 25 weeks(6 h per day and 5 days per week) by dynamic inhalation exposure, while the control group was given dimethyl sulfoxide(DMSO). The 13 weeks or 25 weeks after B[a]P exposure, 24 mice were sacrificed and their lung tissues dissected and observed for tumor formation. During B[a]P exposure, the gas in the poisoning cabinet was collected by the active carbon tube method regularly, and the concentration of B[a]P in the poisoning cabinet was analyzed by gas chromatography mass spectrometer, and the(7 R, 8 S)-dihydroxy-(9 S, 10 R)-epoxy-7, 8, 9, 10-tetrahydrobenzo [a] pyrene(BPDE)-DNA adduct content in the whole blood of mice was determined by ELISA.

Results: Concentration of B[a]P in the dynamic inhalation cabinet was stable at(12. 794±0. 518)μg/m~3. There was no significant difference in the BPDE-DNA content in the experimental objects between 13 weeks and 25 weeks after B[a]P exposure(P>0. 05). After 25 weeks of B[a]P exposure, the lung cancer formation rate in the experimental group was significantly higher than that in the control group(P<0. 05), the tumor formation rate of female mice was up to 100%.

Conclusion: The mice lung cancer model induced by B[a]P dynamic inhalation exposure was established successfully.