Morphology, input-output relations and synaptic connectivity of Cajal-Retzius cells in layer 1 of the developing neocortex of CXCR4-EGFP mice.
Morphology, input-output relations and synaptic connectivity of Cajal-Retzius cells in layer 1 of the developing neocortex of CXCR4-EGFP mice.
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DOI：
10.1007/s00429-013-0627-2
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发表时间：
2014-11
影响因子：
3.1
通讯作者：
Luebke, Joachim H. R.
中科院分区：
文献类型：
--
作者：
Anstoetz, Max;Cosgrove, Kathleen E.;Hack, Iris;Mugnaini, Enrico;Maccaferri, Gianmaria;Luebke, Joachim H. R.
关键词：
第一层（L1）神经元，特别是Cajal-Retzius （CR）细胞是新皮层中最早产生的神经元之一。然而，它们和L1 gaba能中间神经元在早期皮层微回路建立中的作用仍然知之甚少。因此，我们在出生日(P) 7-11岁的CXCR4-EGFP小鼠中研究了全细胞记录和生物细胞素填充的CR细胞的形态，通过其荧光外观可以很容易地识别CR细胞。通过共聚焦显微镜、光学显微镜和随后的电子显微镜来研究它们的发育调节、形态、突触输入输出关系和电生理特性。CR细胞在P4 - P7期间出现高峰，此后在P14时通过细胞凋亡选择性死亡而下降至几乎完全消失。CR细胞在第一层形成了密集的、长距离的水平网络，沿轴突分布着高密度的突触钮扣。它们接受密集的gaba能和非gaba能突触输入，并依次优先通过锥体神经元末端丛树突的棘或轴提供突触输出。有趣的是，在其他物种中，CR细胞与其他皮质神经元之间没有染料偶联，然而，单个CR细胞的生物细胞素标记导致L1端足星形胶质细胞共染色。电生理学上，CR细胞的特点是高输入电阻和特有的放电模式。去极化电流的增加导致动作电位的幅度减小，半宽增加，通常以去极化阻滞终止。膜兴奋性的存在、第1层CR细胞的高密度、它们的远距离水平轴突投射和高密度的突触钮扣以及它们的突触输入输出关系表明，它们是早期皮层网络的组成部分，不仅在第1层中重要，而且对皮层柱的建立和形成也很重要。
Layer 1 (L1) neurons, in particular Cajal–Retzius (CR) cells are among the earliest generated neurons in the neocortex. However, their role and that of L1 GABAergic interneurons in the establishment of an early cortical microcircuit are still poorly understood. Thus, the morphology of whole-cell recorded and biocytin-filled CR cells was investigated in postnatal day (P) 7–11 old CXCR4-EGFP mice where CR cells can be easily identified by their fluorescent appearance. Confocal-, light- and subsequent electron microscopy was performed to investigate their developmental regulation, morphology, synaptic input–output relationships and electrophysiological properties. CR cells reached their peak in occurrence between P4 to P7 and from thereon declined to almost complete disappearance at P14 by undergoing selective cell death through apoptosis. CR cells formed a dense and long-range horizontal network in layer 1 with a remarkable high density of synaptic boutons along their axons. They received dense GABAergic and non-GABAergic synaptic input and in turn provided synaptic output preferentially with spines or shafts of terminal tuft dendrites of pyramidal neurons. Interestingly, no dye-coupling between CR cells with other cortical neurons was observed as reported for other species, however, biocytin-labeling of individual CR cells leads to co-staining of L1 end foot astrocytes. Electrophysiologically, CR cells are characterized by a high input resistance and a characteristic firing pattern. Increasing depolarizing currents lead to action potential of decreasing amplitude and increasing half width, often terminated by a depolarization block. The presence of membrane excitability, the high density of CR cells in layer 1, their long-range horizontal axonal projection together with a high density of synaptic boutons and their synaptic input–output relationship suggest that they are an integral part of an early cortical network important not only in layer 1 but also for the establishment and formation of the cortical column.
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影响因子：
25
作者：
Bystron, Irina;Rakic, Pasko;Blakemore, Colin
通讯作者：
Blakemore, Colin
影响因子：
4.7
作者：
Cosgrove KE;Maccaferri G
通讯作者：
Maccaferri G
影响因子：
2.9
作者：
Chowdhury TG;Jimenez JC;Bomar JM;Cruz-Martin A;Cantle JP;Portera-Cailliau C
通讯作者：
Portera-Cailliau C
影响因子：
56.9
作者：
GUTNICK, MJ;PRINCE, DA
通讯作者：
PRINCE, DA
影响因子：
3.3
作者：
ESCOBAR, MI;PIMIENTA, H;KOSIK, KS
通讯作者：
KOSIK, KS