电磁辐射诱导PC12细胞凋亡中丝裂原活化蛋白激酶的差别激活  

Differential activation of mitogen-activated protein kinase in PC12 cells apoptosis induced by electromagnetic irradiation

作　　者：杨学森[1] 龚茜芬[1] 张广斌[1] 余争平[1] 余晓东[2] 

机构地区：[1]第三军医大学劳动卫生教研室,重庆400038 [2]重庆师范大学动物学重点实验室

出　　处：《中华劳动卫生职业病杂志》2005年第3期167-171,共5页Chinese Journal of Industrial Hygiene and Occupational Diseases

基　　金：国家自然科学基金资助项目(30170237)

摘　　要：目的探讨丝裂原活化蛋白激酶(MAPK)信号转导系统的差别激活与电磁辐射诱导PC12细胞凋亡的关系。方法以65mWcm2电磁波辐照离体培养PC12细胞20min,分为辐照后即刻及3、12、24h共4个观察时相点,采用流式细胞仪检测PC12细胞凋亡率,采用蛋白质免疫印迹法检测ERK12、JNK、P38MAPK蛋白质磷酸化水平。结果电磁波辐照后即刻PC12细胞凋亡开始增加;3h后凋亡细胞进一步明显增多,凋亡率约为23.5%;12h后细胞凋亡率与3h相比,差异无统计学意义(P>0.05);24h后细胞凋亡再次明显增加,并达到高峰。电磁辐射后PC12细胞ERK12和JNK蛋白质磷酸化都明显增加,但ERK12的增加持续到3h,JNK蛋白磷酸化水平增高一直持续到12h,24h后两者都较对照组明显降低。P38MAPK蛋白质磷酸化水平在辐照后一直处于较高水平,其变化趋势呈双峰状,即在3h和24h出现2次磷酸化高峰。结论电磁辐射可以激活MAPK信号转导系统,但ERK12、JNK、P38MAPK表现为差别激活。MAPK信号转导系统可能参与了电磁辐射诱导的PC12细胞凋亡,正是MAPK这种差别激活才导致PC12细胞出现特有的凋亡变化形式。Objective To explore the relationship between differential activation of mitogen-activated protein kinase(MAPK) signal transduction system and apoptosis in PC12 cells induced by electromagnetic irradiation. Methods Cultured PC12 cells were exposed to 65 mW/cm2 electromagnetic wave for 20 min.The PC12 cells apoptosis was detected by flow cytometry 0,3,12,24 h after electromagnetic irradiation.The phosphorylations of ERK1/2,JNK and P38 MAPK were tested by Western-blot. Results Electromagnetic irradiation induced apoptosis in PC12 cells soon after irradiation.The apoptotic rate of PC12 cells increased to about 23.5% at 3 h.But compared with that at 3 h,there was no significant difference in the apoptotic rate at 12 h(P>0.05).The apoptotic rate of PC12 cells increased sharply again at 24 h.After exposure to electromagnetic irradiation,the phosphorylations of ERK1/2 and JNK increased significantly.The increased phosphorylation of ERK1/2 lasted for 3 hours,but of JNK lasted for 12 hours,and 24 hours after irradiation.The phosphorylation of both ERK1/2 and JNK were significantly lower than that of control.The phosphorylation of P38 MAPK was always higher after electromagnetic irradiation,and there were two phosphorylation peaks at 3 h and 24 h. Conclusion The electromagnetic irradiation can induce the activation of MAPK signal transduction system,and ERK1/2,JNK,P38 MAPK showed differential activation.The differential activation of MAPKs may play an important role in the apoptosis of PC12 cells induced by electromagnetic irradiation.

关 键 词：PC12细胞凋亡 丝裂原活化蛋白激酶 辐射诱导 激活 MAPK信号转导系统 差别 P38MAPK ERK1/2 蛋白质免疫印迹法 磷酸化水平 流式细胞仪检测 细胞凋亡率 PCI2细胞 蛋白质磷酸化 电磁辐射 24h JNK 离体培养 凋亡细胞 电磁波 

分 类 号：R594.8[医药卫生—内科学]