Morphological, electrophysiological, and synaptic properties of corticocallosal pyramidal cells in the neonatal rat neocortex
Morphological, electrophysiological, and synaptic properties of corticocallosal pyramidal cells in the neonatal rat neocortex
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DOI：
10.1093/cercor/bhl127
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发表时间：
2007-09-01
期刊：
影响因子：
3.7
通讯作者：
Markram, Henry
中科院分区：
文献类型：
--
作者：
Le Be, Jean-Vincent;Silberberg, Gilad;Markram, Henry
新皮质锥体细胞（PC）投射到各种皮质和皮质下靶点。在第五层，厚簇状PC（TTC）的人口项目的皮质下的目标，如顶盖，脑干和脊髓。另一群V层PC通过胼胝体投射到对侧新皮质半球，介导半球之间的信息传递。这个亚群（皮质胼胝体投射细胞[CCP]）以前已经描述了它们的形态学特性，但对它们的电生理特性知之甚少，它们的突触连接性也是未知的。我们研究了形态学，电生理和突触特性的CCP逆行标记与荧光微珠在P13-P16 Wistar大鼠。CCP的特点是较短，untufted顶端树突，仅达到第二/三层，证实了以前的报告。CCP之间的突触连接与TTC之间观察到的突触连接在发生概率和动态特性上都不同。我们发现，CCP网络的互连比TTC网络少4倍，释放的概率小24%，导致突触传递更加线性。该研究表明，第V层锥体神经元投射到不同的目标，形成子网络与专门的连接配置文件，除了专门的形态和电生理的内在属性。
Neocortical pyramidal cells (PCs) project to various cortical and subcortical targets. In layer V, the population of thick tufted PCs (TTCs) projects to subcortical targets such as the tectum, brainstem, and spinal cord. Another population of layer V PCs projects via the corpus callosum to the contralateral neocortical hemisphere mediating information transfer between the hemispheres. This sub-population (corticocallosally projecting cells [CCPs]) has been previously described in terms of their morphological properties, but less is known about their electrophysiological properties, and their synaptic connectivity is unknown. We studied the morphological, electrophysiological, and synaptic properties of CCPs by retrograde labeling with fluorescent microbeads in P13-P16 Wistar rats. CCPs were characterized by shorter, untufted apical dendrites, which reached only up to layers II/III, confirming previous reports. Synaptic connections between CCPs were different from those observed between TTCs, both in probability of occurrence and dynamic properties. We found that the CCP network is about 4 times less interconnected than the TTC network and the probability of release is 24% smaller, resulting in a more linear synaptic transmission. The study shows that layer V pyramidal neurons projecting to different targets form subnetworks with specialized connectivity profiles, in addition to the specialized morphological and electrophysiological intrinsic properties.