Brown Craig E, Murphy Timothy H
Department of Psychiatry, Brain Research Center University of British Columbia, Vancouver, British Columbia, Canada.
Neuroscientist. 2008 Apr;14(2):139-46. doi: 10.1177/1073858407309854. Epub 2007 Nov 26.
The spontaneous recovery of sensory, motor, and cognitive functions after stroke is thought to be mediated primarily through the reorganization and rewiring of surviving brain circuits. Given that dendritic spine turnover underlies rewiring during normal development and plasticity, this process is likely to play a key role in mediating functional changes that occur during and after stroke. Recently, a new approach has been taken using two-photon microscopy to monitor, in real time, the temporal and spatial progression of dendritic plasticity in the living animal, both while it is experiencing the initial ischemic episode as well as during long-term recovery from stroke damage. Here, we highlight recent evidence showing that stroke can trigger extensive changes in the relatively hardwired adult brain. For example, when dendrites are challenged by acute ischemia, they can disintegrate within minutes of ischemia and rapidly reassemble during reperfusion. Over longer time scales, dendrites in the surviving peri-infarct zone show heightened levels of spine turnover for many weeks after stroke, thereby raising the possibility that future stroke therapies may be able to facilitate or optimize dendritic rewiring to improve functional recovery.
中风后感觉、运动和认知功能的自发恢复被认为主要是通过存活脑回路的重组和重新布线来介导的。鉴于树突棘更新是正常发育和可塑性过程中重新布线的基础，这一过程可能在介导中风期间及之后发生的功能变化中起关键作用。最近，一种新的方法被采用，即使用双光子显微镜实时监测活体动物在经历最初的缺血发作时以及从中风损伤长期恢复过程中树突可塑性的时空进展。在这里，我们强调最近的证据表明中风可引发相对固定的成人大脑中的广泛变化。例如，当树突受到急性缺血挑战时，它们可在缺血几分钟内解体，并在再灌注期间迅速重新组装。在更长的时间尺度上，存活的梗死周围区域的树突在中风后数周内显示出更高水平的棘更新，从而增加了未来中风治疗可能能够促进或优化树突重新布线以改善功能恢复的可能性。
