RETROHIPPOCAMPAL CIRCUITS MEDIATED EPILEPTIFORM ACTIVITY

描述：（改编自研究者摘要）：内嗅皮层 可以产生独立于海马体的癫痫样活动，它可以 维持海马体中产生的癫痫样活动， 这种活动扩散到新皮层。虽然我们一直在紧张地工作， 根据CA3的癫痫样活动和一些现象学研究， 内嗅和海马癫痫发生器的相互作用， 几乎没有人注意到海马后区 这些区域本身会产生癫痫发作活动。部分原因是 一直缺乏关于基本电路和细胞特性的数据， 海马后细胞我们的实验室一直在研究 包括内嗅皮层，前下托， 下托和下托。 这个项目的目的是定义的细胞和内在电路的 内嗅皮层，并确定其作用的产生癫痫样 放电。我们的总体假设是，癫痫样事件（发作间期 棘波和后放电）在内嗅皮层中产生， 未发现板内和板间兴奋性连接的组合 在其他海马后或海马结构中。单个神经元将 电生理学和形态学表征。的性质 单一和复合兴奋性突触后电位将在 识别细胞已识别神经元的细胞和突触特性 将与癫痫样放电期间的活动相关， 去除抑制的切片。 这些结果将为细胞的基本性质提供基础数据， 内嗅皮层及其内在联系这些数据将成为 了解正常和异常生理的基础， 海马后区这些细胞和它们形成的回路的特性 在一种癫痫模型中（在去抑制期间观察到）将证明一些 电路的功能特性。这些功能特性将 为癫痫的发生和发作的扩散提供了重要的见解 内嗅皮层的活动。对这种电路的理解可能会导致 有针对性地限制癫痫发作的发生和传播的实用战略 断开程序。

DESCRIPTION: (Adapted from the Investigator's Abstract): The entorhinal cortex can generate epileptiform activity independent of the hippocampus, it can sustain epileptiform activity generated in the hippocampus, and it gates the spread of such activity to the neocortex. While there has been intensive work on the basis for epileptiform activity in CA3 and some phenomenological studies of the interactions of entorhinal and hippocampal seizure generators, there has been virtually no attention paid to the mechanism by which the retrohippocampal areas generate seizure activity themselves. Part of the reason for this has been a lack of data on the fundamental circuitry and cellular properties of retrohippocampal cells. Our laboratory has been studying the cells and circuits of the retrohippocampal regions, including entorhinal cortex, presubiculum, parasubiculum and subiculum. The aim of this project is to define the cells and intrinsic circuits of the entorhinal cortex and to identify their roles in the generation of epileptiform discharges. Our overall hypothesis is that epileptiform events (interictal spikes and after discharges) are generated in entorhinal cortex by a combination of intralaminar and interlaminar excitatory connections not found in other retrohippocampal or hippocampal structures. Single neurons will be electrophysiologically and morphologically characterized. The properties of unitary and compound excitatory postsynaptic potentials will be examined in identified cells. The cellular and synaptic properties of identified neurons will be correlated with their activity during epileptiform discharges in disinhibited slices. The results will provide fundamental data on the basic properties of cells in the entorhinal cortex and its intrinsic connectivity. These data will be part of the foundation for understanding the normal and abnormal physiology of the retrohippocampal regions. The properties of these cells and circuits they form in one model of epilepsy (that seen during disinhibition) will demonstrate some of the functional properties of the circuitry. These functional properties will provide critical insights into epileptogenesis and the spread of seizure activity in the entorhinal cortex. An understanding of such circuits may lead to practical strategies for limiting seizure generation and spread by targeted disconnection procedures.