SPINAL CORD MATURATION AND LOCOMOTION IN MICE WITH AN ISOLATED CORTEX
SPINAL CORD MATURATION AND LOCOMOTION IN MICE WITH AN ISOLATED CORTEX
复制标题
具有孤立皮质的小鼠的脊髓成熟和运动。
DOI：
10.1016/j.neuroscience.2013.08.057
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发表时间：
2013-12-03
期刊：
影响因子：
3.3
通讯作者：
Zhou, L.
中科院分区：
文献类型：
--
作者：
Han, Q.;Feng, J.;Zhou, L.
脊髓在运动行为中起着关键作用。它传递主要的感觉信息，接收来自脊髓上中心的传入信号，并将运动整合到中央模式发生器中。脊髓运动输出是通过皮质通路（包括皮质脊髓和皮质-皮质下投射）控制的。脊髓损伤会损害脊髓上下行和上行感觉通路。在成年啮齿动物模型中，脊髓的可塑性被认为有助于功能恢复。脊髓功能在多大程度上依赖于皮质输入尚不清楚。在这里，我们使用 Celsr3/Foxg1 小鼠来解决这个问题，其中皮质-皮质下连接（包括皮质脊髓束（CST）和末端感觉通路，丘脑皮质束）在早期发育过程中被基因消除。尽管 Celsr3/Foxg1 小鼠能够进食、行走、在网格上攀爬和游泳，但旷场测试显示它们过于活跃。与正常同窝动物相比，突变动物的脊髓运动神经元数量减少，树突树萎缩。此外，运动轴突末端的数量减少，这一点通过肌电图得到证实。突变脊髓中胆碱能、钙结合蛋白和钙结合蛋白阳性中间神经元的数量适度增加，而 reelin 和小白蛋白阳性中间神经元的数量没有变化。据我们所知，我们的研究提供了第一个遗传证据，证明脊髓运动网络在缺乏皮质连接的情况下不会完全成熟，并且尽管先天性缺乏 CST，但一些运动功能仍然保留。 (C) 2013 国际广播组织。由爱思唯尔有限公司出版。保留所有权利。
The spinal cord plays a key role in motor behavior. It relays major sensory information, receives afferents from supraspinal centers and integrates movement in the central pattern generators. Spinal motor output is controlled via corticofugal pathways including corticospinal and cortico-subcortical projections. Spinal cord injury damages descending supraspinal as well as ascending sensory pathways. In adult rodent models, plasticity of the spinal cord is thought to contribute to functional recovery. How much spinal cord function depends on cortical input is not well known. Here, we address this question using Celsr3/Foxg1 mice, in which cortico-subcortical connections (including corticospinal tract (CST) and the terminal sensory pathway, the thalamocortical tract) are genetically ablated during early development. Although Celsr3/Foxg1 mice are able to eat, walk, climb on grids and swim, open-field tests showed them to be hyperactive. When compared with normal littermates, mutant animals had reduced number of spinal motor neurons, with atrophic dendritic trees. Furthermore, motor axon terminals were decreased in number, and this was confirmed by electromyography. The number of cholinergic, calbindin, and calretinin-positive interneurons was moderately increased in the mutant spinal cord, whereas that of reelin and parvalbumin-positive interneurons was unchanged. As far as we know, our study provides the first genetic evidence that the spinal motor network does not mature fully in the absence of corticofugal connections, and that some motor function is preserved despite congenital absence of the CST. (C) 2013 IBRO. Published by Elsevier Ltd. All rights reserved.