Local and Distant Input Controlling Excitation in Layer II of the Medial Entorhinal Cortex.
Local and Distant Input Controlling Excitation in Layer II of the Medial Entorhinal Cortex.
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DOI：
10.1016/j.neuron.2015.11.029
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发表时间：
2016-01-06
期刊：
影响因子：
16.2
通讯作者：
Monyer H
中科院分区：
文献类型：
--
作者：
Fuchs EC;Neitz A;Pinna R;Melzer S;Caputi A;Monyer H
内侧内嗅皮层（MEC）的第II层（LII）包括支持空间导航的网格细胞。网格细胞的放电模式可以用网络中的吸引子动力学来解释，这需要特定于相位的网格细胞之间的直接兴奋连接或通过中间神经元的间接耦合。然而，关于支持体内活性的局部网络的知识是不完整的。在这里，我们确定了MEC中LII网络的基本组成部分。我们区分了四种类型的兴奋性神经元，表现出细胞类型特异性的局部兴奋性和抑制性连接。此外，我们发现LII神经元有助于相应层对侧神经元的兴奋。最后，我们证明了内侧隔通过两个长程GABA能神经元亚群控制MEC的兴奋，这些神经元靶向LII中不同的中间神经元，从而解除局部回路的抑制。因此，我们确定了本地连接，可以支持吸引子动力学和外部输入，可能会管理激励LII。LII MEC兴奋性神经元可分为四种细胞类型这四种细胞类型表现出特定的局部兴奋性和抑制性连接LII神经元有助于对侧LII神经元的兴奋不同的隔区GABA能神经元在LII MEC中表现出细胞类型特异性抑制内侧内嗅皮层包括在空间导航中起重要作用的网格细胞。Fuchs等人其特征在于基本的兴奋性和抑制性成分的基础网络。这是一个先决条件，开发现实的模型来解释网格细胞的活动。
Layer II (LII) of the medial entorhinal cortex (MEC) comprises grid cells that support spatial navigation. The firing pattern of grid cells might be explained by attractor dynamics in a network, which requires either direct excitatory connectivity between phase-specific grid cells or indirect coupling via interneurons. However, knowledge regarding local networks that support in vivo activity is incomplete. Here we identified essential components of LII networks in the MEC. We distinguished four types of excitatory neurons that exhibit cell-type-specific local excitatory and inhibitory connectivity. Furthermore, we found that LII neurons contribute to the excitation of contralateral neurons in the corresponding layer. Finally, we demonstrated that the medial septum controls excitation in the MEC via two subpopulations of long-range GABAergic neurons that target distinct interneurons in LII, thereby disinhibiting local circuits. We thus identified local connections that could support attractor dynamics and external inputs that likely govern excitation in LII. LII MEC excitatory neurons can be classified into four cell types The four cell types exhibit specific local excitatory and inhibitory connectivity LII neurons contribute to the excitation of contralateral LII neurons Distinct septal GABAergic neurons exhibit cell-type-specific inhibition in LII MEC Medial entorhinal cortex comprises grid cells that play an important role in spatial navigation. Fuchs et al. characterized essential excitatory and inhibitory components of the underlying networks. This is a prerequisite to develop realistic models to explain grid cell activity.