Compartmentalized dendritic plasticity and input feature storage in neurons
Compartmentalized dendritic plasticity and input feature storage in neurons
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DOI：
10.1038/nature06725
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发表时间：
2008-03-27
期刊：
影响因子：
64.8
通讯作者：
Magee, Jeffrey C.
中科院分区：
文献类型：
--
作者：
Losonczy, Attila;Makara, Judit K.;Magee, Jeffrey C.
虽然中枢神经系统中的信息存储被认为主要是由各种形式的突触可塑性介导的，但也有其他机制，如膜兴奋性的改变。局部树突尖峰是由空间聚集和时间同步的突触输入在树突分支内启动的非线性电压事件。局部棘波选择性地只对适当相关的输入作出反应，这使得它们可以作为输入特征检测器，并潜在地作为强大的信息存储机制。然而，目前尚不清楚是否存在任何有效形式的局部树突棘突可塑性。在这里，我们证明了局部树突棘与大鼠海马CA1区锥体神经元胞体之间的偶联可以通过依赖于N-甲基-D-天冬氨酸受体(NMDAR)的树突状Kv4.2钾通道调节以分支特异性的方式被改变。这些数据表明，分支兴奋性的分区变化可以存储突触输入的多种复杂特征，例如它们的时空相关性。我们认为这种“分支强度增强”代表了一种以前未知的信息存储形式，它不同于机制水平和存储信息类型的突触效能变化所产生的信息存储形式。
Although information storage in the central nervous system is thought to be primarily mediated by various forms of synaptic plasticity, other mechanisms, such as modifications in membrane excitability, are available. Local dendritic spikes are nonlinear voltage events that are initiated within dendritic branches by spatially clustered and temporally synchronous synaptic input. That local spikes selectively respond only to appropriately correlated input allows them to function as input feature detectors and potentially as powerful information storage mechanisms. However, it is currently unknown whether any effective form of local dendritic spike plasticity exists. Here we show that the coupling between local dendritic spikes and the soma of rat hippocampal CA1 pyramidal neurons can be modified in a branch- specific manner through an N- methyl- D- aspartate receptor ( NMDAR)- dependent regulation of dendritic Kv4.2 potassium channels. These data suggest that compartmentalized changes in branch excitability could store multiple complex features of synaptic input, such as their spatio- temporal correlation. We propose that this 'branch strength potentiation' represents a previously unknown form of information storage that is distinct from that produced by changes in synaptic efficacy both at the mechanistic level and in the type of information stored.