利用单细胞凝胶电泳技术研究镉对鲫鱼淋巴细胞DNA的损伤

Detection of DNA Damage in Carassius Auratus Lymphocytes Induced by Cadmium with Single Cell Gelelectrophoresis Assay

以鲫鱼作为受试生物,采用单细胞凝胶电泳技术,研究了不同浓度及不同染毒时间氯化镉对鲫鱼淋巴细胞DNA的损伤。结果显示,各氯化镉染毒组DNA平均迁移长度明显增加,与阴性对照组比较差异有显著性(P<0.05);另外,随着氯化镉染毒剂量的增加,各剂量组DNA的平均迁移长度逐渐增加,在实验浓度范围内,存在明显的剂量-效应关系(P<0.01),但未见明显的时间-效应关系。氯化镉可引起鲫鱼淋巴细胞DNA损伤,鲫鱼淋巴细胞DNA损伤可望成为一个较好的水环境基因毒剂指标。

This study was designed to assess whether cadmium chloride could induce DNA damage in lymphocytes of Carassius auratus using single cell gelelectrophoresis (SCGE) assay. 60 Carassius auratua were randomly divided into ten groups with 6 Carassius auratus in each group. For dose-effect groups, the Carassius auratus were injected intraperitoneally with 0.125, 0.313, 0.626 and 1.250 mg·kg-1 water solution of cadmium chloride respectively for 24 h, and a negative control group was set up. At the concentration of 1.250 mg·kg-1, four time-effect groups (12, 24, 48 and 72 h) and a zero time control group were setup. The samples of 1.5 mL blood were obtained in testing time for SCGE assay. The results showed that the average length of DNA migration in all cadmium chloride exposed groups was significantly higher than that of negative control group (P<0.05) and increased gradually with the dose increasing of cadmium chloride. There existed dose-effect relationship, but no time-effect relationship among the tested concentrations (P<0.01). Cadmium chloride could induce DNA damage in lymphocytes of Carassius auratus which might be a better gene toxicant index in water.