Differential Inputs to the Perisomatic and Distal-Dendritic Compartments of VIP-Positive Neurons in Layer 2/3 of the Mouse Barrel Cortex.
Differential Inputs to the Perisomatic and Distal-Dendritic Compartments of VIP-Positive Neurons in Layer 2/3 of the Mouse Barrel Cortex.
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DOI：
10.3389/fnana.2016.00124
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发表时间：
2016
影响因子：
2.9
通讯作者：
Hioki H
中科院分区：
文献类型：
--
作者：
Sohn J;Okamoto S;Kataoka N;Kaneko T;Nakamura K;Hioki H
由兴奋性和抑制性神经元组成的递归网络是新皮层功能的基础。哺乳动物新皮层中的抑制性神经元在分子上是多样的，并且单个细胞类型在新皮层微回路中发挥独特的功能作用。最近，血管活性肠多肽阳性（VIP+）神经元，包括抑制性神经元的一个亚类，引起了特别的关注，因为它们可以通过抑制其他类型的抑制性神经元，如小白蛋白-（PV+）和生长抑素阳性（SOM+）抑制性神经元，促进感觉信息处理来解除对锥体细胞的抑制。虽然VIP+神经元已被报道接受来自PV+和SOM+抑制性神经元以及来自皮层和丘脑兴奋性神经元的突触输入，但这些突触输入的体树突定位尚未在亚细胞空间分辨率下阐明。在本研究中，我们可视化层（L）2/3 VIP+神经元的体树突膜注射到桶皮质的VIP-Cre基因敲入小鼠的新开发的腺相关病毒（AAV）载体，我们确定了广泛的分支VIP+神经元树突的垂直方向。共聚焦激光扫描显微镜观察发现，VIP+神经元的突触接触点分布不均匀，主要分布在体周区（距胞体<100 μm）和远端-树突区（距胞体≥100 μm）。皮质和丘脑皮质兴奋性神经元优先针对VIP+神经元的远端树突隔室。另一方面，SOM+和PV+抑制性神经元优先靶向远端树突和VIP+神经元的体周区室，分别。值得注意的是，VIP+神经元几乎没有相互连接。这些观察结果表明SOM+和PV+神经元输入对VIP+神经元活性的不同抑制作用; SOM+神经元的抑制性输入可能调节树突中局部的兴奋性输入，而PV+神经元可以通过VIP+神经元的体周域的神经支配有效地干扰动作电位的产生。本研究显示了位点特异性输入的精确结构，为VIP+神经元突触输入的整合机制提供了结构基础。
The recurrent network composed of excitatory and inhibitory neurons is fundamental to neocortical function. Inhibitory neurons in the mammalian neocortex are molecularly diverse, and individual cell types play unique functional roles in the neocortical microcircuit. Recently, vasoactive intestinal polypeptide-positive (VIP+) neurons, comprising a subclass of inhibitory neurons, have attracted particular attention because they can disinhibit pyramidal cells through inhibition of other types of inhibitory neurons, such as parvalbumin- (PV+) and somatostatin-positive (SOM+) inhibitory neurons, promoting sensory information processing. Although VIP+ neurons have been reported to receive synaptic inputs from PV+ and SOM+ inhibitory neurons as well as from cortical and thalamic excitatory neurons, the somatodendritic localization of these synaptic inputs has yet to be elucidated at subcellular spatial resolution. In the present study, we visualized the somatodendritic membranes of layer (L) 2/3 VIP+ neurons by injecting a newly developed adeno-associated virus (AAV) vector into the barrel cortex of VIP-Cre knock-in mice, and we determined the extensive ramification of VIP+ neuron dendrites in the vertical orientation. After immunohistochemical labeling of presynaptic boutons and postsynaptic structures, confocal laser scanning microscopy revealed that the synaptic contacts were unevenly distributed throughout the perisomatic (<100 μm from the somata) and distal-dendritic compartments (≥100 μm) of VIP+ neurons. Both corticocortical and thalamocortical excitatory neurons preferentially targeted the distal-dendritic compartment of VIP+ neurons. On the other hand, SOM+ and PV+ inhibitory neurons preferentially targeted the distal-dendritic and perisomatic compartments of VIP+ neurons, respectively. Notably, VIP+ neurons had few reciprocal connections. These observations suggest different inhibitory effects of SOM+ and PV+ neuronal inputs on VIP+ neuron activity; inhibitory inputs from SOM+ neurons likely modulate excitatory inputs locally in dendrites, while PV+ neurons could efficiently interfere with action potential generation through innervation of the perisomatic domain of VIP+ neurons. The present study, which shows a precise configuration of site-specific inputs, provides a structural basis for the integration mechanism of synaptic inputs to VIP+ neurons.
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影响因子：
16.2
作者：
Blatow, M;Rozov, A;Monyer, H
通讯作者：
Monyer, H
影响因子：
3.3
作者：
Hioki, H;Fujiyama, F;Kaneko, T
通讯作者：
Kaneko, T
影响因子：
2.5
作者：
Hioki, Hiroyuki;Nakamura, Hisashi;Kaneko, Takeshi
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Kaneko, Takeshi
影响因子：
2.9
作者：
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Zilles, K
影响因子：
64.8
作者：
ECKENSTEIN, F;BAUGHMAN, RW
通讯作者：
BAUGHMAN, RW