Molecular and cellular mechanisms of defective neural network rhythm generation

在本项目中，我们主要试图利用自发性突变神经小鼠，分析海马、丘脑、大脑皮层和小脑皮层中导致癫痫和小脑性共济失调等神经症状的网络机制。我们在癫痫性钙通道突变小鼠“蹒跚”中发现了丘脑皮质投射前馈电路的缺陷。我们证明突触传递的缺陷以发育依赖的方式出现。我们尝试使用多电极细胞外记录系统检测癫痫样放电，但我们未能获得稳定一致的结果。直到最近，膜片钳对脑切片的记录大多来自单个神经元。由于很难理解局部网络的活动，我们开始使用双膜片钳和三膜片钳记录。利用这一先进的系统，我们阐明了丘脑神经元同步活动所需的基本神经线路模式（手稿正在准备中）。我们也对钙通道突变的形态学影响感兴趣。我们采用逆行标记浦肯野神经元，并开发分析软件定量测量浦肯野细胞树突乔枝的版图和分支。除了体外脑切片记录外，还必须记录体内的神经活动。我们开发了一种体内记录系统。我们现在正在对正常小鼠和突变小鼠进行比较。

In this project, we mainly tried to analyze network mechanisms in the hippocampus, thalamus, cerebral cortex and cerebellar cortex, which underlie neurological symptoms such as epilepsy and cerebellar ataxia, using spontaneous mutant neurological mice.We identified a defect in the feedforward circuit of the thalamocortical projection in epileptic calcium channel mutant mice 'tottering'. We demonstrated the defect of synaptic transmission appears in a development-dependent manner. We tried to detect epileptiform discharges using a multi-electrode extracellular recording system, but we failed to obtain stable and consistent results.Until recently, patch clamp recordings from brain slice preparations are mostly from single neurons. Because it is difficult to understand activity of the local network, we started to double- and triple-patch clamp recordings. With this advanced system, we elucidated the basic neural wiring pattern that is required for synchronized activity of thalamic neurons (manuscript in preparation).We were also interested in the morphological impacts of calcium channel mutations. We used retrograde labeling of Purkinje neurons, and developed analysis software to quantitatively measure the territory and branching of Purkinje cell dendritic arbors. In addition to in vitro brain slice recordings, it is essential to record neural activity in vivo. We developed a system for in vivo recording. We are now making comparison between normal and mutant mice.