Saleha Banu B, Ishaq Mohd, Danadevi K, Padmavathi P, Ahuja Y R
Department of Genetics, Osmania University, Hyderabad 500 007, Andhra Pradesh, India.
Food Chem Toxicol. 2004 Dec;42(12):1931-6. doi: 10.1016/j.fct.2004.07.007.
Single stranded DNA breaks induced by copper sulfate (CuSO(4)) in mice has been studied in vivo using Alkaline Single Cell Gel Electrophoresis (Comet assay). Mice were administered orally with doses of 0, 1.25, 2.50, 5.00, 7.50, 10.00 and 12.50 mg/kg body weight (b.wt.) of CuSO4 respectively. The samples of whole blood were collected at 24, 48, 72 h, first week and second week post-treatment and the assay was carried out to determine single strand DNA breaks as represented by comet tail-length. In addition, the sample was used to study the repair efficiency by incubating the samples with RPMI medium for 2 h. Results indicated a significant DNA damage at all the doses after treatment with CuSO4 when compared to controls showing a clear dose-dependent response (p < 0.05). A gradual decrease in the tail-lengths from 48 h post-treatment was observed and by second week, the values returned to control levels at all doses. The study on the repair efficiency indicated that mice treated with all the doses of CuSO4 showed decrease in mean comet tail-length indicating repair efficiency capacity but less when compared to those of controls. The study also reveals that comet assay is a sensitive and rapid method for detecting DNA damage caused by trace metals such as copper (Cu).
利用碱性单细胞凝胶电泳（彗星试验）在体内研究了硫酸铜（CuSO₄）诱导的小鼠单链DNA断裂情况。分别给小鼠口服剂量为0、1.25、2.50、5.00、7.50、10.00和12.50毫克/千克体重（b.wt.）的CuSO₄。在治疗后24、48、72小时、第一周和第二周采集全血样本，并进行试验以确定由彗星尾长表示的单链DNA断裂情况。此外，通过将样本与RPMI培养基孵育2小时来研究修复效率。结果表明，与对照组相比，用CuSO₄处理后所有剂量下均出现显著的DNA损伤，呈现明显的剂量依赖性反应（p < 0.05）。观察到治疗后48小时起尾长逐渐缩短，到第二周时，所有剂量下的值均恢复到对照水平。对修复效率的研究表明，用所有剂量的CuSO₄处理的小鼠平均彗星尾长均缩短，表明具有修复能力，但与对照组相比修复能力较弱。该研究还表明，彗星试验是检测铜（Cu）等痕量金属引起的DNA损伤的一种灵敏且快速的方法。
