1-溴丙烷致中国仓鼠肺细胞hprt基因位点突变作用研究

Study on hprt locus mutation in Chinese hamster lung cells induced by 1-bromopropane

目的探讨1-溴丙烷(1-BP)对中国仓鼠肺细胞(V79)次黄嘌呤鸟嘌呤磷酸核糖转移酶(hprt)基因位点的致突变作用。方法将V79分为大鼠肝微粒体混合功能氧化酶(S9)代谢活化系和非S9代谢活化系,每系各设3.375、6.750、13.500 g/L 3个不同质量浓度的1-BP实验组;另设1.000 g/L甲磺酸乙酯阳性对照组(非S9代谢活化系)、0.001g/L甲基硝基亚硝基胍阳性对照组(S9代谢活化系)和溶剂对照组,溶剂对照组加等体积的无血清培养基。染毒时间为6 h。应用细胞克隆检测法检测V79 hprt基因位点的突变率。结果非S9代谢活化系,1-BP实验组突变率与溶剂对照组比较,差异均无统计学意义(P>0.05);S9代谢活化系,3.375、6.750 g/L 1-BP实验组突变率均高于溶剂对照组,差异均有统计学意义(P<0.01),但不存在剂量-反应关系。结论 1-BP经代谢活化后可能对V79 hprt基因位点具有致突变作用。

Objective To study the effect of 1-bromopropane （1-BP） on hprt locus mutation in Chinese hamster lung cells. Methods The hprt locus mutation was examined at different dose levels of 1-BP in absence and presence of S9 （ -S9 and ＋ S9 ） metabolic activation system. V79 cells were treated with 1-BP at the doses of 3. 375, 6. 750, 13. 500 g/L for 6 hours respectively. 1. 000 g/L EMS （-S9） and 0. 001 g/L MNNG （ ＋ S9） were given as the positive control groups, while serum free medium was designed to the negative control groups. The mutant frequency was counted by cell-cloning. Results Under the condition of - S9 metabolic activation system, the differences of mutant frequency among all treatment groups and solvent control group were not significant （P 〉 0. 05 ）. When S9 metabolic activation system was added, the mutant frequencies in 3. 375 g/L and 6. 750 g/L treatment groups were significantly higher than those in solvent control group （ P 〈 0. 01 ）, but without dose-re- sponse relationship. Conclusion In the presence of S9 metabolic activation system, 1-BP might induce hprt locus mutation in V79 cells.