Qiu Lian-bo, Ding Gui-rong, Zhang Ya-mei, Zhou Yan, Wang Xiao-wu, Li Kang-chu, Xu Sheng-long, Tan Juan, Zhou Jia-xing, Guo Guo-zhen
Department of Radiation Medicine, Faculty of Preventive Medicine, Fourth Military Medical University, Xi'an 710032, China.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2009 Sep;27(9):539-43.
To study the effect of electromagnetic pulse (EMP) on the permeability of blood-brain barrier, tight junction (TJ)-associated protein expression and localization in rats.
66 male SD rats, weighing (200 approximately 250) g, were sham or whole-body exposed to EMP at 200 kV/m for 200 pulses. The repetition rate was 1 Hz. The permeability of the blood-brain barrier in rats was assessed by albumin immunohistochemistry. The expression of typical tight junction protein ZO-1 and occludin in both cerebral cortex homogenate and cerebral cortex microvessel homogenate was analyzed by the Western blotting and the distribution of ZO-1 and occludin was examined by immunofluorescence microscopy.
In the sham exposure rats, no brain capillaries showed albumin leakage, at 0.5 h after 200 kV/m EMP exposure for 200 pulses; a few brain capillaries with extravasated serum albumin was found, with the time extended, the number of brain capillaries with extravasated serum albumin increased, and reached the peak at 3 h, then began to recover at 6 h. In addition, no change in the distribution of the occludin was found after EMP exposure. Total occludin expression had no significant change compared with the control. However, the expression level of ZO-1 significantly decreased at 1 h and 3 h after EMP exposure in both cerebral cortex homogenate and cerebral cortex microvessel homogenate. Furthermore, immunofluorescence studies also showed alterations in ZO-1 protein localization in cerebral cortex microvessel.
The EMP exposure (200 kV/m, 200 pulses) could increase blood-brain barrier permeability in rat, and this change is associated with specific alterations in tight junction protein ZO-1.
研究电磁脉冲（EMP）对大鼠血脑屏障通透性、紧密连接（TJ）相关蛋白表达及定位的影响。
选取66只体重（200～250）g的雄性SD大鼠，分为假暴露组和全身暴露组，全身暴露组大鼠接受200 kV/m的EMP照射200个脉冲，重复频率为1 Hz。采用白蛋白免疫组化法评估大鼠血脑屏障的通透性。通过蛋白质免疫印迹法分析大脑皮质匀浆和大脑皮质微血管匀浆中典型紧密连接蛋白ZO-1和闭合蛋白的表达，并通过免疫荧光显微镜检查ZO-1和闭合蛋白的分布。
假暴露组大鼠脑毛细血管未见白蛋白渗漏；200 kV/m的EMP照射200个脉冲后0.5 h，可见少量脑毛细血管有血清白蛋白外渗，随着时间延长，有血清白蛋白外渗的脑毛细血管数量增多，3 h时达到高峰，6 h时开始恢复。此外，EMP照射后闭合蛋白的分布未见改变。与对照组相比，闭合蛋白的总表达无显著变化。然而，EMP照射后1 h和3 h，大脑皮质匀浆和大脑皮质微血管匀浆中ZO-1的表达水平均显著降低。此外，免疫荧光研究还显示大脑皮质微血管中ZO-1蛋白的定位发生了改变。
EMP照射（200 kV/m，200个脉冲）可增加大鼠血脑屏障的通透性，且这种变化与紧密连接蛋白ZO-1的特异性改变有关。
