Ames试验与HPRT试验两种方法对6种氧化型染发剂的检测

Testing of six oxidative hair dyes using the Ames and the HPRT tests

目的:通过细菌回复突变试验(Ames试验)和体外哺乳动物细胞基因突变试验(HPRT试验)两种方法检测氧化型染发剂,并对其结果进行分析比较,探讨两种方法在检测氧化型染发剂致突变性中的应用。方法:Ames试验采用一组营养缺陷型鼠伤寒沙门氏菌检测6种氧化型染发剂。各受试物分别设4个可供分析的剂量组,剂量范围从312~10 000μg/皿,通过计算受试物回复突变菌落数,判定受试物的致突变性。HPRT试验采用体外培养的V79细胞,各受试物分别设4个可供分析的剂量组,剂量范围从4.88~5 000μg/mL,研究6种氧化型染发剂致细胞HPRT位点突变的频率,通过计算受试物引起的V79细胞的突变频率,判定其致突变性。结果:在Ames试验中,无论加与不加体外代谢活化系统,受试物在2 500~10 000μg/皿剂量范围均存在回变菌落数超过溶剂对照组两倍的情况,并有剂量-反应关系,表明Ames试验检测6种氧化型染发剂均为阳性结果。而在HPRT试验中,无论加与不加体外代谢活化系统,各受试物在>2 500μg/mL时具有明显毒性作用,在9.75~2 500μg/mL剂量范围细胞突变频率与阴性对照组比较,差异均无统计学意义,表明HPRT试验检测6种氧化型染发剂均为阴性结果。结论:由于氧化型染发剂有明显的细胞毒性,导致HPRT试验无法设计更高的剂量,从而无法反映受试物致突变性的真实水平。而Ames试验具有简单、快速、经济等优点,可作为检测氧化型染发剂致突变性的首选方法。

OBJECTIVE:To use the Ames and the HPRT tests,six oxidative hair dyes were tested,and application of the two methods in detecting mutagenicity of oxidative hair dyes was discussed.METHODS: Four dose groups, ranging from 312 to 10 000 μg/dish were set up for the Ames test.mutagenicity was determined by calculating the numbers of reverted mutant colonies. In the HPRT test,V79cells were cultured in vitro,and 4 dose groups were set up for analysis,with the dose range from 4.88 to5 000 μg/mL,to determine mutation frequencies of the HPRT sites. RESULTS:With or without an in vitro metabolic activation system in the Ames assay,the numbers of retroactive colonies in the treated groups were more than twice that of the solvent control group,and there was a dose-effect relationship. However,there was no statistically significant difference in cell mutation frequencies between the treated and the control group with or without the metabolic activation system. CONCLUSION:Due to cytotoxicity of the oxidative hair dyes to mammalian cells, the HPRT test was not capable of detecting mutagenicity of the hair dyes. Thus, the Ames test which is simple,rapid and economical,and can be used as the first choice for mutagenicity test.