Effects of pregabalin and thrombospondins on enhanced excitatory connectivity, new synapse formation and epileptogenesis after neocortical injury

描述（由申请方提供）：加巴喷丁和血小板反应蛋白对新皮层损伤后兴奋性连接增强、新突触形成和癫痫发生的影响，大脑皮层和海马神经元之间新兴奋性布线的萌芽、神经胶质细胞的变化和兴奋性突触的形成是脑损伤的结果，被认为有助于动物模型和人脑中的癫痫。没有有效的预防性治疗可用于预防脑损伤后的癫痫发生。计划中的实验集中在一种新的方法，用于限制皮质创伤后兴奋性连接增加和癫痫的发展。星形胶质细胞分泌的血小板反应蛋白（TSPs）在发育过程中和皮层损伤后参与新的兴奋性突触的形成。实验将检验以下假设：普瑞巴林（PGB）（Lyrica），一种经批准的干扰TSP与其α 2 δ-1受体结合的药物，将减少兴奋性突触形成和发芽，并限制癫痫样活动的发展。PGB和TSP的作用将在未处理小鼠、TSP“敲除”小鼠和α 2 delta-1过表达癫痫小鼠的致癫痫新皮质损伤的部分皮质隔离（“底切”，UC）模型中进行探索。癫痫样活动的发生率记录在体外皮质 将使用电生理学和解剖学技术测量损伤后的切片、轴突的发芽、兴奋性突触的密度和网络连接性。笼状谷氨酸的激光扫描光刺激将与全细胞记录结合使用，以绘制皮质切片中的兴奋性连接。过度的神经元活动和TSP、α 2 δ-1受体和新突触形成的增加之间可能存在的联系将在幼稚或受伤的皮层中进行研究。将评估体内皮质损伤后PGB治疗对这些指标的影响，以检验药物将减少脑创伤后结构和功能异常并导致癫痫发生的假设。.相关性：创伤后癫痫是严重的新皮层或海马损伤的显著后果，其改变了神经元和胶质细胞的结构和功能，并诱导皮层回路的过度兴奋。不幸的是，治疗往往是无效的，在缓解癫痫发作，一旦他们发生，没有药物是可用的，将防止癫痫的过程，导致创伤后癫痫。这些实验的结果将有助于理解皮层损伤的细胞和电路效应，并提供有关加巴喷丁和普瑞巴林预防脑损伤后癫痫发展的潜在作用的新信息。

DESCRIPTION (provided by applicant): The effects of gabapentin and thrombospondins on enhanced excitatory connectivity, new synapse formation and epileptogenesis after neocortical injury sprouting of new excitatory wiring between neurons in cerebral cortex and hippocampus, changes in glial cells and formation of excitatory synapses are consequences of brain injury that are thought to contribute to epilepsy in animal models and human brain. There is no effective prophylactic treatment available to prevent epileptogenesis after brain injury. The planned experiments focus on a new approach for limiting the development of the increased excitatory connections and epilepsy after cortical trauma. Astrocyte-secreted thrombospondins (TSPs) are involved in new excitatory synapse formation during development and after cortical injury. Experiments will test the hypothesis that pregabalin (PGB) (Lyrica), an approved drug that interferes with the binding of TSPs to their alpha2delta-1 receptor, will decrease excitatory synapse formation and sprouting and limit development of epileptiform activity. The effects of PGB and TSPs will be explored in the partial cortical isolation ("undercut", UC) model of epileptogenic neocortical injury in na�ve mice, in TSP "knockout" mice and alpha2delta-1 overexpressing epileptic mice. The incidence of epileptiform activity recorded in in vitro cortical slices after injury, sprouting of axons, density of excitatory synapses and network connectivity will be measured using electrophysiological and anatomical techniques. Laser scanning photostimulation of caged glutamate will be used in conjunction with whole cell recordings to map excitatory connections in cortical slices. A possible link between excessive neuronal activity and increases in TSPs, the alpha2delta-1 receptor and new synapse formation will be studied in na�ve or injured cortex. The effects of PGB treatment after cortical injury in vivo on these measures will be assessed to test the hypothesis that the drug will decrease the structural and functional abnormalities that follow brain trauma and lead to the development of epilepsy. . Relevance: Posttraumatic epilepsy is a prominent consequence of serious neocortical or hippocampal injury that alters neuronal and glial structure and function and induces hyperexcitability in cortical circuits. Unfortunately, treatment is often ineffective at relieving seizures once they occur and no drug is available that will prevent the epileptogenic processes that lead to posttraumatic epilepsy. Results of these experiments will contribute to understanding cellular and circuit effects of cortical injury, and provide new information about a potential role for gabapentin and pregabalin to prevent development of epilepsy after brain injury.