重金属胁迫对罗非鱼血细胞DNA损伤的影响

DNA Damage in Hemocytes of Tilapia(Oreochromis niloticus)Induced by Heavy Metals with SCGE Technique

为研究重金属对鱼类的毒性效应,将罗非鱼血细胞分别暴露于低、中、高三种不同浓度的四种重金属溶液Cr(VI)、Pb、Cu、Hg中2 h,采用单细胞凝胶电泳实验(彗星电泳)技术检测血细胞的DNA损伤程度,对照组不加任何重金属,检测指标包括尾部DNA含量、尾长、尾矩、Olive尾矩.结果显示,鱼血细胞对四种重金属胁迫均极为敏感,随重金属胁迫浓度的升高,DNA损伤程度增加.因此,罗非鱼可作为评价重金属污染遗传毒性损伤的敏感性生物标记物.

To investigate the toxic effects of heavy metal on marine fish,hemocytes of Oreochromis niloticus were respectively exposed to four kinds solution— Cr(Ⅵ),Pb,Cu and Hg,each with three concentrations.Then the DNA damage to hemolymph cells was detected by single cell gel electrophoresis(comet assay) after two hours,whereas the control group did not add any heavy metal.The detection indexes include tail DNA content,tail length,tail moment and Olive tail moment.Results showed that blood cells were highly sensitive to the four kinds of heavy metal.Furthermore,with the increase of the concentration of heavy metal,the degree of DNA damage increased.Therefore,Oreochromis niloticus can be a sensitive biological marker to evaluate the genetic toxicity effects of heavy metals.