电磁脉冲辐射诱导小鼠成纤维细胞系NIH/3T3凋亡的研究

Study on apoptosis of fibroblast cell line NIH/3T3 induced by electromagnetic pulse radiation

目的 研究电磁脉冲 (EMP)辐射对小鼠成纤维细胞系 (NIH/ 3T3)凋亡的影响 ,并探讨EMP对生物体损伤的可能机制。方法 利用场强为 6 0kV/m的EMP照射细胞后 ,采用细胞计数、MTT比色法、流式细胞术及免疫组化染色等方法 ,分别观察EMP对HIN/ 3T3细胞的活力、凋亡以及Bcl 2和 p5 3蛋白表达等的影响。对免疫组化染色阳性的细胞 ,在高倍镜下用CMIAS II图像 -分析系统进行图像分析 ,所有数据均经SPSS8.0软件进行分析。结果 EMP可明显抑制NIH/ 3T3细胞的增殖与活力 (P <0 .0 5 ) ;非贴壁细胞率在辐射后明显增加 ,6h达高峰 (33.9% ) ,并可诱导细胞明显凋亡 ,6h达高峰 (15 .0 7% )。图像分析结果表明 ,EMP辐射后 ,有不同程度的Bcl 2蛋白表达的下调及 p5 3蛋白表达的上调 (P <0 .0 5 )。结论 EMP可诱导NIH/ 3T3细胞凋亡及Bcl 2及p5 3蛋白异常表达 ,提示Bcl 2及p5 3可能参与了NIH/

Aim To study the effect of electromagnetic pulse (EMP) radiation in a dose of 60 kV/m (electric field intensity), 20 ns (rise time) and 25 μs (pulse wide) on apoptosis of NIH/3T3 fibroblasts, and to explore the possible machanism of the injury to organisms caused by EMP. Methods After the NIH/3T3 cells were exposed to EMP, the proliferation and viability of NIH/3T3 fibroblasts were estimated by hemacytometer and MTT colorimetry. Apoptosis rate was analysed by flow cytometry. The immnohistochemical SP staining was used to determine the expression of bcl 2, and p53 protein. The positively stained cells were analyzed with CMIAS II image analysis system statistical analysis was performed with SPSS8.0 software. Results The proliferation and viability of NIH/3T3 cells were markedly inhibited and significant apoptosis of the cells could be induced following exposing to EMP. EMP could increase the percentage of non adherent cells and the of non adherent cells reached its peak (33.9%) at 6 hrs after EMP. The highest ratie of apoptosis was 15.07% at 6 hrs, and then decreased gradually. CMIAS II image analysis system showed that down regulation of Bcl 2 and up regulation of p53 with varying degrees could be induced by EMP ( P <0.05). Conclusion EMP can induce apoptosis of NIH/3T3 fibroblasts; EMP can also down regulate Bcl 2 level and up regulate p53 level in NIH/3T3 fibroblasts. The bcl 2 and the p53 genes may take part in the process of apoptosis of NIH/3T3 cells.