Physiological Properties of Supragranular Cortical Inhibitory Interneurons Expressing Retrograde Persistent Firing
Physiological Properties of Supragranular Cortical Inhibitory Interneurons Expressing Retrograde Persistent Firing
复制标题
DOI：
10.1155/2015/608141
复制
发表时间：
2015-01-01
影响因子：
3.1
通讯作者：
Mittmann, Thomas
中科院分区：
文献类型：
--
作者：
Imbrosci, Barbara;Neitz, Angela;Mittmann, Thomas
神经元是极化的功能单位。体树突区室接受并整合突触输入，而轴突则以动作电位（AP）的形式长距离传递相关的突触信息。尽管这一概念被广泛接受，但最近的研究表明，在某些情况下，轴突也可以在远离索马的轴突部位产生独立于突触输入的AP。这些异位的AP既向突触终末行进，又逆向地向索马行进。这种不寻常的形式的神经元通信似乎优先发生在皮层抑制性中间神经元后，一段时间的强烈的神经元活动，并可能有深远的影响神经元的信息处理。在这里，我们表明，列车异位产生的AP可以诱导在新皮层2/3层GABA能中间神经元的大部分体细胞去极化诱导数百个AP。稀疏发生的异位尖峰也观察到在一个大部分的第1层中间神经元，即使在没有事先体细胞去极化。值得注意的是，我们发现，产生异位AP的中间神经元显示特定的膜和形态学特性显着不同于其余的GABA能细胞，因此可能代表一个功能独特的中间神经元亚群。
Neurons are polarized functional units. The somatodendritic compartment receives and integrates synaptic inputs while the axon relays relevant synaptic information in form of action potentials (APs) across long distance. Despite this well accepted notion, recent research has shown that, under certain circumstances, the axon can also generate APs independent of synaptic inputs at axonal sites distal from the soma. These ectopic APs travel both toward synaptic terminals and antidromically toward the soma. This unusual form of neuronal communication seems to preferentially occur in cortical inhibitory interneurons following a period of intense neuronal activity and might have profound implications for neuronal information processing. Here we show that trains of ectopically generated APs can be induced in a large portion of neocortical layer 2/3 GABAergic interneurons following a somatic depolarization inducing hundreds of APs. Sparsely occurring ectopic spikes were also observed in a large portion of layer 1 interneurons even in absence of prior somatic depolarization. Remarkably, we found that interneurons which produce ectopic APs display specific membrane and morphological properties significantly different from the remaining GABAergic cells and may therefore represent a functionally unique interneuronal subpopulation.