A modified mini-stroke model with region-directed reperfusion in rat cortex
A modified mini-stroke model with region-directed reperfusion in rat cortex
复制标题
大鼠皮层区域定向再灌注的改良迷你中风模型
DOI：
10.1038/sj.jcbfm.9600591
复制
发表时间：
2008-05-01
影响因子：
6.3
通讯作者：
Luo, Qingming
中科院分区：
文献类型：
--
作者：
Luo, Weihua;Wang, Zhen;Luo, Qingming
局部特定大脑区域的微小缺血促进了对中风大脑恢复机制的理解。然而，传统的小卒中模型采用永久性动脉结扎，但缺乏可控再灌注，这对于延迟功能恢复的结果至关重要。在这项研究中，我们设计了一种新的大鼠迷你中风模型，其中血管结扎可以轻松逆转以诱导靶向再灌注。具体来说，在传统的小动脉结扎中加入了一个柔性环，以收紧结扎环，并有利于切割结扎线，以便随后进行充分的再灌注。使用激光散斑对比成像直接通过颅窗探索脑血流的分布。一个明显的缺血核心，非常适合结扎环的轮廓，其边界是半影区，然后在涉及环的动脉结扎后立即被非缺血组织一起包围。切断结扎线后，先前的缺血核心发生再通后过度灌注，并且在再灌注后24小时发生更大程度的过度灌注。相比之下，传统小中风模型中颈总动脉的再循环几乎没有改变缺血核心内的低灌注状态。来自两种对照组的证据表明，该环可能对底层皮层产生压缩作用，然后导致通过氯化三苯基四唑染色鉴定出的更高度局部化的梗塞。我们的数据表明，该模型为研究急性中风和康复中的神经血管动力学提供了机会，特别是利用新兴的光学成像技术。
Mini-ischemia localized into a specific brain area has promoted understanding of the mechanisms underlying brain recovery in stroke. However, the conventional mini-stroke model adopted permanent arterial ligations but lacked controllable reperfusion, which is crucial for the outcome of delayed functional recovery. In this study, we devised a new rat mini-stroke model in which the vascular ligations can be easily reversed to induce targeted reperfusion. Specifically, a flexible ring was incorporated into the conventional small arterial ligations to tighten the ligating loops and facilitate cutting the ligatures for sufficient reperfusion afterwards. The distribution of cerebral blood flow was explored directly through a cranial window using laser speckle contrast imaging. A distinct ischemic core, which well fits the profile of the ligated ring, was bordered by a penumbral zone and then together surrounded by nonischemic tissue immediately after the arterial ligations involving the ring. After cutting the ligatures, post-recanalization hyperperfusion occurred in the previous ischemic core and to a greater extent at 24 h after reperfusion. In contrast, recirculation of common carotid artery in the conventional mini-stroke model hardly altered hypoperfusion status within the ischemic core. Evidence from two kinds of control groups indicated that the ring might produce a compression effect on the underlying cortex and then contribute to the more highly localized infarct that was identified by triphenyltetrazolium chloride staining. Our data suggest that this model provides opportunities for investigating the neurovascular dynamics in acute stroke and rehabilitation, especially with emerging optical imaging techniques.