Electrical compartmentalization in dendritic spines.
Electrical compartmentalization in dendritic spines.
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DOI：
10.1146/annurev-neuro-062111-150455
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发表时间：
2013-07
影响因子：
13.9
通讯作者：
R. Yuste
中科院分区：
文献类型：
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作者：
R. Yuste
中枢神经系统中的大多数兴奋性输入都会接触树突棘，避开树突轴，因此树突棘必须在神经元中发挥关键作用。最近的数据表明，除了增强连通性和隔离突触生物化学之外，树突棘还可以充当独立于其母体树突的电室。越来越清楚的是，尽管树突棘在动作电位（AP）期间经历的电压与树突的电压相似，但在兴奋性突触后电位（EPSP）期间，棘必须比树突轴承受更高的去极化。突触电位可能在脊柱头部被放大，然后当它们通过脊柱颈部侵入树突时被减弱。这些电变化可能是由于被动和主动机制的组合所致，可能会通过许多输入的联合激活来防止树突饱和，影响树突整合，并有助于快速突触可塑性。脊柱的电特性可以使神经回路利用高连接性，实现“突触民主”，其中每个输入都可以单独集成、统计和修改，以生成紧急功能状态。
Most excitatory inputs in the CNS contact dendritic spines, avoiding dendritic shafts, so spines must play a key role for neurons. Recent data suggest that, in addition to enhancing connectivity and isolating synaptic biochemistry, spines can behave as electrical compartments independent from their parent dendrites. It is becoming clear that, although spines experience voltages similar to those of dendrites during action potentials (APs), spines must sustain higher depolarizations than do dendritic shafts during excitatory postsynaptic potentials (EPSPs). Synaptic potentials are likely amplified at the spine head and then reduced as they invade the dendrite through the spine neck. These electrical changes, probably due to a combination of passive and active mechanisms, may prevent the saturation of dendrites by the joint activation of many inputs, influence dendritic integration, and contribute to rapid synaptic plasticity. The electrical properties of spines could enable neural circuits to harness a high connectivity, implementing a "synaptic democracy," where each input can be individually integrated, tallied, and modified in order to generate emergent functional states.