Wang T C, Lee M L
Institute of Zoology, Academia Sinica, Taipei 115, Taiwan, ROC.
Mutat Res. 2001 Nov 15;498(1-2):79-87. doi: 10.1016/s1383-5718(01)00271-6.
Inconsistent results among reports on cadmium genotoxicity revealed that certain confounding factors might significantly influence the outcomes of assessment. In Chinese hamster ovary (CHO-W8) cells, chromosome aberration induced by six different cadmium compounds was found positively associated with intracellular cadmium concentration. A parallel association was also observed among different CHO strains treated with same cadmium compound, the cadmium acetate. Both the cadmium-induced chromosome aberration and cadmium uptake were influenced by the presence of fetal calf serum (FCS). The presence of 10% FCS during the 2h treatment period greatly retarded the cellular cadmium uptake, and concurrently reduced the chromosome aberration induction. Other factors such as specific cadmium anion involved and the duration of cadmium treatment period in the investigation also influenced the assessment results of cadmium-induced chromosome aberration. In the protocol with a 2h pulse treatment, cadmium acetate, chloride and sulfate induced more chromosome aberration than cadmium nitrate, carbonate and oxide. When cadmium was present in the culture of the entire treatment period for 18 h, the results went the opposite way. Cadmium nitrate, carbonate and oxide induced significant chromosome aberration, while other three cadmium compounds gave negative results. Cadmium compounds did not induce significant SCE at the same dose level that yielded significant chromosome aberration induction, either in the protocol with the short pulse or long treatment period.
关于镉遗传毒性的报告结果不一致，这表明某些混杂因素可能会显著影响评估结果。在中国仓鼠卵巢（CHO-W8）细胞中，发现六种不同镉化合物诱导的染色体畸变与细胞内镉浓度呈正相关。在用相同镉化合物醋酸镉处理的不同CHO细胞株中也观察到了类似的相关性。镉诱导的染色体畸变和镉摄取都受到胎牛血清（FCS）的影响。在2小时处理期间存在10% FCS会极大地阻碍细胞对镉的摄取，同时减少染色体畸变的诱导。调查中涉及的其他因素，如特定的镉阴离子以及镉处理期的持续时间，也会影响镉诱导染色体畸变的评估结果。在2小时脉冲处理方案中，醋酸镉、氯化镉和硫酸镉诱导的染色体畸变比硝酸镉、碳酸镉和氧化镉更多。当镉在整个18小时处理期的培养物中存在时，结果则相反。硝酸镉、碳酸镉和氧化镉诱导了显著的染色体畸变，而其他三种镉化合物则给出了阴性结果。在短脉冲或长处理期方案中，镉化合物在产生显著染色体畸变诱导的相同剂量水平下并未诱导显著的姐妹染色单体交换。
