重金属Cu、Pb对泥鳅(Misgurnus anguillicaudatus)卵细胞凋亡及DNA损伤的SCGE试验

采用室内暴露试验方法,以单细胞凝胶电泳技术(SCGE)检测,研究了Cu、Pb不同浓度梯度与不同暴露时间联合染毒对泥鳅卵细胞DNA的损伤.结果表明,各Cu、Pb浓度组DNA平均迁移长度增加,与阴性对照组比较差异有显著性(P＜0.05).此外,随着Cu、Pb染毒剂量的增加,各试验组DNA的平均迁移长度逐渐增加,在试验浓度梯度范围内(Cu 0.01mg/L+Pb 0.05mg/L、Cu 0.10mg/L+Pb 0.50mg/L、Cu 0.25mg/L+Pb 0.75mg/L),存在较为显著的剂量-效应关系(P＜0.05),但未见明显的时间-效应关系(P＞0.05).Cu、Pb可引起泥鳅卵细胞凋亡和DNA损伤,卵细胞的不同损伤水平可望作为较为理想的水环境基因毒性指标.

SCGE TEST OF OOCYTES APOPTOSIS AND DNA DAMAGE ON LOACHES MISGURNUS ANGUILLICAUDATUS BY HEAVY METAL Cu AND Pb

With the method of single cell gel electrophoresis (SCGE), the test studied the DNA damage to the loach oocytes, which suffered different concentration of joint attacking of Cu and Pb with various exposure time and doses. The results showed that the average migration length of the DNA increased in each concentration group that was treated by both Cu and Pb. The significant differences appeared as compared with the negative control group (P<0.05). In addition, with the contamination doses enhanced, the average migration length of DNA increased gradually in each treatment group. It was obvious that the relationship of dose-effect existed (P<0.05), but there is no distinct relationship of time-effect (P>0.05) in the gradient range of concentration (Cu 0.01mg/L + Pb 0.05mg/L, Cu 0.10mg/L + Pb 0.50mg/L, Cu 0.25mg/L + Pb 0.75mg/L). As a conclusion, the joint toxicity of Cu and Pb can cause apoptosis and DNA damage to the oocytes and the level of damage will be ideal index for water environment genetic toxicity.