Principles Governing the Operation of Synaptic Inhibition in Dendrites
Principles Governing the Operation of Synaptic Inhibition in Dendrites
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DOI：
10.1016/j.neuron.2012.05.015
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发表时间：
2012-07-26
期刊：
影响因子：
16.2
通讯作者：
Segev, Idan
中科院分区：
文献类型：
--
作者：
Gidon, Albert;Segev, Idan
突触抑制在塑造神经元网络的动力学和选择细胞组装中起着关键作用。通常，抑制性轴突接触其靶神经元的特定树突子域，在那里它通常形成10-20个突触，有时在非常远的分支上。这种连接模式的功能含义还没有得到很好的理解。我们的实验为基础的理论研究突出了几个新的和违反直觉的原则，树突状抑制。我们发现，远端的“关闭路径”，而不是近端的“路径”抑制有效地抑制近端可兴奋的树突“热点”，从而有力地控制神经元的输出。此外，在多个突触接触的情况下，抑制作用在全球范围内发挥作用，从抑制性突触向心性传播数百微米。因此，在缺乏抑制性突触的区域中的抑制可能超过突触位点本身的抑制。这些结果提供了新的见解的协同作用，树突状抑制在控制树突的兴奋性和可塑性，并在动态塑造功能树突的亚结构域和它们的输出。
Synaptic inhibition plays a key role in shaping the dynamics of neuronal networks and selecting cell assemblies. Typically, an inhibitory axon contacts a particular dendritic subdomain of its target neuron, where it often makes 10-20 synapses, sometimes on very distal branches. The functional implications of such a connectivity pattern are not well understood. Our experimentally based theoretical study highlights several new and counterintuitive principles for dendritic inhibition. We show that distal "off-path" rather than proximal "on-path" inhibition effectively dampens proximal excitable dendritic "hotspots," thus powerfully controlling the neuron's output. Additionally, with multiple synaptic contacts, inhibition operates globally, spreading centripetally hundreds of micrometers from the inhibitory synapses. Consequently, inhibition in regions lacking inhibitory synapses may exceed that at the synaptic sites themselves. These results offer new insights into the synergetic effect of dendritic inhibition in controlling dendritic excitability and plasticity and in dynamically molding functional dendritic subdomains and their output.