论文部分内容阅读
目的研究50Hz电磁场暴露对小鼠睾丸细胞DNA以及精子染色质结构的影响。方法将昆明种雄性小鼠暴露于0.2mT或6.4mT、50Hz电磁场中,持续4周,分别采用单细胞凝胶电泳法和精子染色质结构检测法分析睾丸细胞DNA断裂情况以及精子染色质结构。结果经电磁场暴露后,0.2、6.4mT组睾丸细胞彗星的相对尾长、彗尾相对DNA含量分别为17.86%±14.60%、2.32%±4.26%及17.88%±13.71%、2.35%±3.87%,与对照组(13.06%±12.38%、1.52%±3.25%)相比,均有明显上升,差异有统计学意义(P<0.05)。0.2、6.4mT组发生DNA迁移的细胞百分率分别为37.83%、39.38%,对照组为25.64%。流式细胞术对精子染色质结构检测的结果表明,S.D.αT(αT分布标准偏差)、XαT(αT均值)没有发生明显变化,但COMPαT(主群以外的精子占总精子的百分数)与对照组相比,有上升的趋势。结论极低频电磁场可引发睾丸细胞DNA链断裂增加,可能引起精子核染色质浓缩异常。
Objective To study the effects of 50 Hz electromagnetic field exposure on the DNA and sperm chromatin structure of testicular cells in mice. Methods Kunming male mice exposed to 0.2mT or 6.4mT, 50Hz electromagnetic field for 4 weeks, single cell gel electrophoresis and sperm chromatin structure detection method were used to analyze DNA fragmentation and chromatin structure of testis. Results After exposure to electromagnetic field, the relative tail length and relative DNA content of comet tail in testis of 0.2 and 6.4 mT group were 17.86% ± 14.60%, 2.32% ± 4.26% and 17.88% ± 13.71%, 2.35% ± 3.87%, respectively, Compared with the control group (13.06% ± 12.38%, 1.52% ± 3.25%), there was a significant increase, the difference was statistically significant (P <0.05). The percentage of cells with DNA migration in 0.2 and 6.4 mT groups were 37.83% and 39.38%, respectively, and 25.64% in control group. The results of flow cytometry on the chromatin structure of sperm showed that SDαT (standard deviation of αT distribution) and XαT (αT mean) did not change significantly, but COMPαT (percentage of total sperm outside the main group in total sperm) In contrast, there is an upward trend. Conclusion Electromagnetic field in very low frequency can induce the increase of DNA strand breaks in testicular cells, which may lead to the abnormal chromatin condensation in sperm.