Regulation of conduction time along axons.
Regulation of conduction time along axons.
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DOI：
10.1016/j.neuroscience.2013.06.047
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发表时间：
2014-09-12
期刊：
影响因子：
3.3
通讯作者：
Seidl AH
中科院分区：
文献类型：
--
作者：
Seidl AH
及时传递信息对于神经系统的正常运作至关重要。运动技能、感觉统合和认知功能的正确发挥需要神经传导速度的精确调节。在脊椎动物中，信号沿神经纤维的快速传输是通过轴突的髓鞘形成以及兰维尔结节之间的跳跃式传导实现的。髓鞘是一种特化的神经胶质细胞，由中枢神经系统中的少突胶质细胞提供。髓鞘形成不仅使传导速度最大化，还提供了一种系统地调节神经系统传导时间的方法。沿着轴突系统地调节传导速度，从而系统地调节神经区之间的传导时间，是神经系统中常见的现象。到目前为止，人们对系统传导速度调节和传导时间同步的机制知之甚少。节点组装、节点间距离(节点间距)和轴突直径--所有决定信号沿轴突传播速度的参数--都由髓鞘胶质细胞控制。因此，神经胶质细胞和神经元之间存在相互作用。这篇综述总结了神经系统中传导速度受轴突解剖变异调节的例子。虽然这些系统的功能暗示并不总是明确的，但最近对鸟类和哺乳动物听觉系统的研究提供了具有高时间精度和明确的生物功能的系统中传导速度调节的例子。总之，这些发现表明了一个活跃的过程，它塑造了轴突和髓鞘胶质细胞之间的相互作用，从而控制了轴突的传导速度。未来涉及这些系统的研究可能会进一步深入了解大脑中特定的传导时间是如何在发育过程中建立和维持的。在整个文本中，传导速度用于信号传播的速度，即动作电位传播的速度。传导时间是指特定的信号从起源到目标，即神经元胞体到轴突终末所需的时间。
Timely delivery of information is essential for proper function of the nervous system. Precise regulation of nerve conduction velocity is needed for correct exertion of motor skills, sensory integration and cognitive functions. In vertebrates, the rapid transmission of signals along nerve fibers is made possible by the myelination of axons and the resulting saltatory conduction in between nodes of Ranvier. Myelin is a specialization of glia cells and is provided by oligodendrocytes in the central nervous system. Myelination not only maximizes conduction velocity, but also provides a means to systematically regulate conduction times in the nervous system. Systematic regulation of conduction velocity along axons, and thus systematic regulation of conduction time in between neural areas, is a common occurrence in the nervous system. To date, little is understood about the mechanism that underlies systematic conduction velocity regulation and conduction time synchrony. Node assembly, internode distance (node spacing) and axon diameter - all parameters determining the speed of signal propagation along axons - are controlled by myelinating glia. Therefore, an interaction between glial cells and neurons has been suggested. This review summarizes examples of neural systems in which conduction velocity is regulated by anatomical variations along axons. While functional implications in these systems are not always clear, recent studies in the auditory system of birds and mammals present examples of conduction velocity regulation in systems with high temporal precision and a defined biological function. Together these findings suggest an active process that shapes the interaction between axons and myelinating glia to control conduction velocity along axons. Future studies involving these systems may provide further insight into how specific conduction times in the brain are established and maintained in development. Throughout the text, conduction velocity is used for the speed of signal propagation, i.e. the speed at which an action potential travels. Conduction time refers to the time it takes for a specific signal to travel from its origin to its target, i.e. neuronal cell body to axonal terminal.
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DOI：
10.1523/jneurosci.2176-12.2012
发表时间：
2012-10-10
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience
影响因子：
--
作者：
Anderson S;Parbery-Clark A;White-Schwoch T;Kraus N
通讯作者：
Kraus N
影响因子：
64.8
作者：
BAKER, GE;STRYKER, MP
通讯作者：
STRYKER, MP
影响因子：
64.8
作者：
Court, FA;Sherman, DL;Brophy, PJ
通讯作者：
Brophy, PJ
影响因子：
64.5
作者：
DEWAEGH, SM;LEE, VMY;BRADY, ST
通讯作者：
BRADY, ST
影响因子：
11
作者：
BRILL, MH;WAXMAN, SG;JOYNER, RW
通讯作者：
JOYNER, RW