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现已证明,妇女在妊娠头三个月服用二乙基己烯雌酚后,可通过胎盘传迁给子代,引起女性阴道或子宫透明细胞癌。炔雌醇和二乙基己烯雌酚一样同属甾体激素,有必要考察其致癌性。由于突变剂多数是致癌剂,故可通过测定其致突变性预测其致癌性。Ames试验作为致癌物质初筛的最优方法和预警系统已为科学家所公认。本实验用Ames方法测定了炔雌醇的致突变性。鼠伤寒沙门氏组氨酸缺陷型菌株TA_(98),TA_(100),TA_(1535),TA_(1537),TA_(1538)经检定具有组氨酸缺陷;脂多糖屏障丢失;切除修复系统缺失及自发突变的特性;此外TA_(98),TA_(100)还具有R因子。以上5项指标均符合Ames原菌株的特点,因此可供试验用。用不同浓度炔雌醇和一些已知突变剂共同对照进行试验。在点样定性试验中对照强突变剂N-甲基-N-硝基-N-亚硝基胍(MNNG)呈现阳性突变反应,但炔雌醇未见阳性反应。在标准平板试验中炔雌醇呈现
It has been shown that after taking diethylstilbestrol in the first trimester of pregnancy, women can pass on to the offspring through the placenta and cause clear cell carcinoma of the vagina or uterus in women. Ethinyl estradiol and diethylstilbestrol are the same steroid hormones, it is necessary to examine its carcinogenicity. Since most mutagens are carcinogenic agents, their carcinogenicity can be predicted by measuring their mutagenicity. Ames test as a carcinogen precursor screening method and the best early warning system has been recognized by scientists. In this experiment, Ames method was used to determine the mutagenicity of ethinylestradiol. The tyrosinase tyrosine tyrosine TA_ (98), TA_ (100), TA_ (1535), TA_ (1537), TA_ (1538) were identified as having histidine deficiency, Missing and spontaneous mutation characteristics; In addition TA_ (98), TA_ (100) also has R factor. The above five indicators are in line with the characteristics of Ames original strain, so can be used for testing. Experiments were conducted with different concentrations of ethinylestradiol and some known mutants. In the spot-like qualitative test, the control mutants N-methyl-N-nitro-N-nitrosoguanidine (MNNG) showed a positive mutation reaction, but ethinylestradiol showed no positive reaction. Ethinyl estradiol is present in standard plate trials