CAJ | 학술논문

目的研究电磁脉冲(electromagnetic pulse,EMP)辐照对大鼠血脑屏障通透性及血脑屏障紧密连接(tight junction,TJ)相关蚩白的影响.方法 66只健康成年雄性SD大鼠按体重随机分为假辐照组和辐照组.EMP辐照参数为:场强200 kV/m,脉宽7 ns,脉冲次数200,脉冲重复频率1 Hz.辐照后不同时间取材,用白蛋白免疫组织化学方法观察EMP辐照后血脑屏障通透性的变化,免疫印迹法检测脑组织和脑微血管中TJ蚩白(occludin和ZO-1)的表达情况,免疫荧光方法观察微血管紧密连接蛋白的分布情况.结果免疫组织化学结果显示,辐照后0.5 h即可见有白蛋白漏出的微血管,但数目较少,随辐照后时间延长,有白蛋门漏出的微血管数目逐渐增加,至辐照后3 h达到高峰,辐照后6 h时开始恢复,辐照后12 h基本恢复至对照水平;免疫印迹结果显示,occludin蛋白水平与对照组相比无明显差异;ZO-1蛋白水平在辐照后1、3 h明显降低,并且免疫荧光结果显示ZO-1在微血管上的分布亦发生了改变,由辐照前的连续分布变为断续分布.结论 EMP辐照后ZO-1蛋白水平和分布的改变可能是EMP致大鼠血脑屏障通透性增加的分子机制之一.
목적 연구전자맥충(electromagnetic pulse,EMP)복조대대서혈뇌병장통투성급혈뇌병장긴밀련접(tight junction,TJ)상관치백적영향.방법 66지건강성년웅성SD대서안체중수궤분위가복조조화복조조.EMP복조삼수위:장강200 kV/m,맥관7 ns,맥충차수200,맥충중복빈솔1 Hz.복조후불동시간취재,용백단백면역조직화학방법 관찰EMP복조후혈뇌병장통투성적변화,면역인적법검측뇌조직화뇌미혈관중TJ치백(occludin화ZO-1)적표체정황,면역형광방법 관찰미혈관긴밀련접단백적분포정황.결과 면역조직화학결과 현시,복조후0.5 h즉가견유백단백루출적미혈관,단수목교소,수복조후시간연장,유백단문루출적미혈관수목축점증가,지복조후3 h체도고봉,복조후6 h시개시회복,복조후12 h기본회복지대조수평;면역인적결과 현시,occludin단백수평여대조조상비무명현차이;ZO-1단백수평재복조후1、3 h명현강저,병차면역형광결과 현시ZO-1재미혈관상적분포역발생료개변,유복조전적련속분포변위단속분포.결론 EMP복조후ZO-1단백수평화분포적개변가능시EMP치대서혈뇌병장통투성증가적분자궤제지일.
Objective 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. Methods 66 male SD rats, weighing (200～250) 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 im-munohistochemistry. 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 distri-bution of ZO-1 and oceludin was examined by immunofluoreseenee microscopy. Results In the sham expo-sure 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 oeeludin was found after EMP exposure. Total occludin ex-pression had no significant change compared with the control. However, the expression level of ZO-1 signifi-cantly decreased at 1 h and 3 h after EMP exposure in both cerebral cortex homogenate and cerebral cortex microvessel homogenate. Furthermore, immunofluorescenee studies also showed alterations in ZO-1 protein lo-calization in cerebral cortex microvessel. Conclusion The EMP exposure (200 kV/m, 200 pulses) could in-crease blood-brain barrier permeability in rat, and this change is associated with specific alterations in tight junction protein ZO-1.