Severe blood-brain barrier disruption and surrounding tissue injury.
Severe blood-brain barrier disruption and surrounding tissue injury.
复制标题
DOI：
10.1161/strokeaha.109.551341
复制
发表时间：
2009-12
期刊：
影响因子：
8.3
通讯作者：
Lyden PD
中科院分区：
文献类型：
--
作者：
Chen B;Friedman B;Cheng Q;Tsai P;Schim E;Kleinfeld D;Lyden PD
缺血期间血脑屏障开放呈双相时间进程，可能部分可逆，并使血浆成分进入大脑且可能损伤细胞。相比之下，缺血后的严重血管破坏不太可能可逆，甚至会使潜在有害的血浆成分进一步渗出。我们试图使用简单的荧光示踪剂对严重受损的血管进行大规模可视化，并确定这种血管破坏是否与严重的实质损伤区域共定位。
通过大脑中动脉短暂闭塞（tMCAo）1、2、4或8小时，然后再灌注30分钟，在成年Sprague Dawley大鼠中造成严重的血管破坏和缺血性损伤。在闭塞前静脉注射异硫氰酸荧光素 - 葡聚糖（2 MDa）。灌注固定后，对脑切片进行超微结构或荧光成像处理。我们通过对濒死细胞进行氟金染色确定了组织损伤的早期证据。
随着缺血持续时间的增加，大量高分子量葡聚糖 - FITC以一种特征性模式侵入并标记缺血区域，首先出现在内侧纹状体，扩散到外侧纹状体，最后累及皮质；在顶叶中部区域可见损伤最严重，这与该模型中已知的缺血区域一致。严重血管破坏的区域分布与24小时氯化三苯基四氮唑（TTC）苍白区域的分布相关（r = 0.75，p < 0.05），也与细胞死亡标记物氟金的分布相关（r = 0.86，p < 0.05）。超微结构检查显示，与低渗漏区域以及对侧同源区域相比，高渗漏区域中肿胀的星形胶质细胞足突和肿胀的线粒体面积显著增加（方差分析p < 0.01）。从闭塞2小时到8小时，葡聚糖渗出到基底膜和周围组织的情况显著增加（独立样本t检验，p < 0.05）。
用高分子量葡聚糖 - FITC渗漏标记的严重血管破坏与严重的组织损伤相关。这种严重血管破坏的标记物可能有助于进一步研究血管破坏介导的组织损伤的病理解剖机制。
Blood brain barrier opening during ischemia follows a biphasic time course, may be partially reversible, and allows plasma constituents to enter brain and possibly damage cells. In contrast, severe vascular disruption after ischemia is unlikely to be reversible and allows even further extravasation of potentially harmful plasma constituents. We sought to use simple fluorescent tracers to allow wide-scale visualization of severely damaged vessels and determine whether such vascular disruption co-localized with regions of severe parenchymal injury. Severe vascular disruption and ischemic injury was produced in adult Sprague Dawley rats by transient occlusion of the middle cerebral artery (tMCAo) for 1, 2, 4, or 8 hours, followed by 30min reperfusion. Fluorescein isothiocyanate-dextran (2 MDa) was injected intravenously prior to occlusion. After perfusion-fixation, brain sections were processed for ultra-structure or fluorescence imaging. We identified early evidence of tissue damage with Fluoro-Jade staining of dying cells. With increasing ischemia duration, greater quantities of high molecular weight dextran-FITC invaded and marked ischemic regions in a characteristic pattern, appearing first in the medial striatum, spreading to the lateral striatum, and finally involving cortex; maximal injury was seen in the mid-parietal areas, consistent with the known ischemic zone in this model. The regional distribution of the severe vascular disruption correlated with the distribution of 24-hour TTC pallor (r=0.75, p<0.05) and the cell death marker Fluoro-Jade (r = 0.86, p<0.05). Ultrastructural examination showed significantly increased areas of swollen astrocytic foot process and swollen mitochondria in regions of high compared to low leakage, and compared to contralateral homologous regions (ANOVA p<0.01). Dextran extravasation into the basement membrane and surrounding tissue increased significantly from 2 to 8 hours of occlusion duration (Independent samples t-test, p<0.05). Severe vascular disruption, as labeled with high molecular weight dextran-FITC leakage, is associated with severe tissue injury. This marker of severe vascular disruption may be useful in further studies of the patho-anatomic mechanisms of vascular-disruption mediated tissue injury.