eNOS解偶联对大脑中动脉栓塞后大鼠神经血管单元的作用及机制

发布时间：2018-04-30 11:03

本文选题：神经血管单元 + 内皮型一氧化氮合酶　；参考：《中风与神经疾病杂志》2017年06期

【摘要】：目的探讨大鼠大脑中动脉栓塞模型中,内皮型一氧化氮合酶(e NOS)解偶联对神经血管单元的作用及机制。方法将80只雄性SD大鼠随机分为假手术组(n=40)和大脑中动脉栓塞(MCAO)组(n=40)。参照Longa法制作MCAO模型。栓塞后6 h,通过蛋白印记法检测缺血区e NOS不同偶联状态的表达情况及3-硝基酪氨酸(3-NT)的水平;通过尼氏染色比较缺血区神经元的形态及存活情况;通过免疫组织化学染色比较缺血区星形胶质细胞、微血管内皮细胞以及血脑屏障紧密连接对应的标记物GFAP、VWF、Occludin的表达水平;通过MRI的T2加权序列和动脉自旋标记(ASL)反应栓塞后脑组织病灶范围及血流情况。结果 MCAO后栓塞部位在T2序列上呈高信号,在ASL序列上血流信号减低。e NOS二聚体/单体的比例明显低于假手术组(P0.05);3-NT的含量明显高于假手术组(P0.05)。尼氏染色显示MCAO后神经元大量空泡形成,核固缩变性,数量显著减少;免疫组化结果显示,VWF、Occludin的表达较假手术组明显减少,而GFAP则明显增多(P0.05)。结论 MCAO会导致e NOS解偶联。e NOS解偶联后NO合成受限,而具有毒性作用的3-NT产生增多,炎症反应加重,从而对神经血管单元结构及功能产生破坏作用。
[Abstract]:Objective to investigate the effect and mechanism of endothelial nitric oxide synthase (Enos) uncoupling on neurovascular units in rat middle cerebral artery embolization (MCAE) model. Methods 80 male Sprague-Dawley rats were randomly divided into sham operation group (n = 40) and MCAO group (n = 40). MCAO model was made by referring to Longa method. At 6 h after embolization, the expression of e NOS in different coupling states and the level of 3-nitrotyrosine 3-NTwere detected by protein imprinting, and the morphology and survival of neurons in ischemic area were compared by Nissl staining. Immunohistochemical staining was used to compare the expression levels of glial cells, microvascular endothelial cells and the corresponding marker GFAP-VFF-Occludin in ischemic area. T2-weighted sequence of MRI and arterial spin labeling (ASL) were used to reflect the focus and blood flow of cerebral tissue after embolization. Results the location of embolization after MCAO showed high signal intensity on T2 sequence, and the ratio of blood flow signal decreased. E NOS dimer / monomer on ASL sequence was significantly lower than that in sham operation group (P 0.05) and the content of 3-NT was significantly higher than that in sham operation group (P 0.05). Nissl's staining showed that after MCAO, a large number of vacuoles were formed, and the number of neurons denatured by pyknosis was decreased significantly, while the expression of VWF- Occludin was significantly lower than that of sham-operated group, while the expression of VWF- Occludin was significantly increased in GFAP group than that in sham-operated group (P 0.05). Conclusion MCAO can cause no synthesis to be restricted after uncoupling of e NOS. E NOS, but 3-NT with toxic effect will be increased and inflammatory reaction will be aggravated, which will destroy the structure and function of neurovascular units.
【作者单位】：陕西中医药大学;中国人民解放军陆军总医院神经内科;中国人民解放军第四五一医院神经内科;
【分类号】：R743.3

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