摘要:应用体外染色体畸变试验研究CTD能否引起培养的哺乳动物细胞的染色体畸变,以评价其潜在的致突变性。根据预试验的结果,确定本试验的浓度分别为0.44、0.22及0.11mg/mL。同时设立阴性对照组(去离子水)和阳性对照组。在加入或不加入代谢活化系统(S9)的条件下,使培养的中国仓鼠肺成纤文细胞(以下简称CHL细胞)暴露于试验样品中,染毒后6h和24h,收获细胞经低渗固定后滴片并染色。每个剂量组选200个分散良好的中期分裂相细胞进行染色体畸变分析。CTD在0.11、0.22及0.44mg/mL剂量下,在染毒6h加S9时的不含裂隙的染色体畸变率分别为0.50%、3.00%及1.50%,染毒6h不加S9时的不含裂隙的染色体畸变率分别为1.50%、0.50%及0.00%,染毒24h不加S9时的不含裂隙的染色体畸变率均为1.00%,与阴性对照组比较其差异均无统计学意义(P>0.05)。阳性对照组染毒6h加S9、染毒6h不加S9及染毒24h不加S9的不含裂隙的染色体畸变率分别为33.00%、41.00%及41.50%,与阴性对照组相比有统计学差异(P<0.05)。在本试验条件下,考察有无S9条件下,CTD分别在0.44、0.22及0.11mg/mL剂量时,对CHL细胞无诱发染色体畸变的效应。29721 毕业论文关键字: CTD;CHL细胞;染色体畸变
Effects of CTD on CHL chromosomal aberration
Abstract:According to the literature ‘OECD Guideline for the testing of chemicals 473: In Vitro Mammalian Chromosome aberration test(21st July 1997)’ to research if CTD can cause chromosome aberration of cultured mammalian cells, to evaluate their potential mutagenicity. According to the preliminary test results,We determine the concentration of the test set respectively for 0.44、0.22 及0.11mg/mL. To establish the negative control group(deionized water) and the positive control group at the same time. Put the training of Chinese hamster lung fibroblast (hereinafter referred to as CHL cells) exposed to the test sample with and without metabolic activation system (S9).Get the cells after hypotonic fixation and staining drop after 6h and 24h. Select 200 well scattered metaphase cell from each dose group to be used as chromosome aberration analysis. Under the doses of 0.11mg/ml, 0.22mg/ml and 0.44mg/ml without S9, the cells’ chromosome aberration rate without fracture is1.5%、0.50% and 0.00% after 6h;and 1.00% after 24h. We also get the result that the cell’ chromosome aberration rate is 0.5%、3.00% and 1.50% after 6h under the same condition just with S9. Compared with the negative control group, we can find the differences were not statistically significant (P>0.05). Relatively, in the positive control group we find the cells’ chromosome aberration rate is 33.00%、41.00% and 41.50% after 6h with S9, 6h without S9, 24h without S9.Compared with the negative control group, we can find the differences were statistically significant (P>0.05). CHL cells can’t be Induced distortion under the conditions of this experiment, no matter CTD in 0.44,0.22 and 0.11mg/mL doses, with and without S9 .
Key words:CTD;CHL cell;Chromosomal Aberration test
目录
1 绪论 1
1.1 染色体概念简介 1
1.2 染色体的化学组成 1
1.3 染色体的结构和功能的相互关系 2
1.4 染色体畸变 3
1.4.1 染色体数目异常的类型 3
1.4.2 染色体结构异常 4
2 应用背景及研究进展 5
2.1 应用背景 5
2.2 研究进展 5
2.2.1 各类遗传毒性试验发展概况 5
2.2.2 体外染色体畸变试验 6
2.2.3 体外染色体畸变试验优缺点 7