二氯甲烷不同途径染毒对小鼠骨髓细胞微核率的影响

The effect of different exposure route of dichloromethane on micronucleus rate of bone marrow in mice

目的通过比较不同途径染毒的小鼠骨髓细胞微核实验,探讨二氯甲烷(DCM)的遗传毒性。方法通过连续染毒5天的静式吸入和灌胃给予DCM,分别于末次染毒后6h和24h取股骨骨髓常规制片。结果在经呼吸道染毒的小鼠骨髓细胞微核试验中,高浓度组(16mg/L)小鼠骨髓细胞微核率与阴性对照组比较有极显著性差异(P<0.01),中浓度组(8mg/L)和低浓度组(4mg/L)小鼠骨髓细胞微核率与阴性对照组比较也有显著性差异(P<0.05)。在剂量4～16mg/L之间,小鼠骨髓微核率由4.0‰上升至15.0‰,呈明显的剂量反应关系。在经灌胃染毒的小鼠骨髓细胞微核试验中,随着剂量的增加,小鼠骨髓细胞微核率也有不同程度的增加,与阴性对照组比较有显著性差异。末次染毒后6h采样结果与24h采样无显著性差异(P>0.05)。结论经呼吸道和消化道给予一定剂量的DCM均能明显增加小鼠骨髓嗜多染红细胞(PCE)的微核率,且微核率的增加并没有性别差异。

Objective To investigate the genetic toxicity ofdichloromethylene （DCM） by comparison ofmicronucleus rate of bone marrow in mice exposed to DCM through different route. Methods The experiment was carried out with Kunming mice. The mice was divided into 2 groups and exposed to DCM in two ways （inhalation and ingestion）. The mice inhaled DCM at the concentrations of 16 mg/L,8 mg/L,4 mg/L and 0 mg/L （negative） respectively 2 hours each day for 5 days or ingested DCM at the dose of 660mg/kg, 330mg/kg, 165mg/kg and oil （negative） daily for 5 days. Bone marrow samples were taken 6 and 24 hours after the last dose of DCM. Results A significant dose - dependent increase in micronucleus rate of bone marrow was observed in inhalation and ingestion groups as compared with negative control group （ P 〈 0.05 ） , especially in the inhalation group. Conclusion Inhalation and ingestion of DCM has mutagenicity.