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

描述（由申请人提供）：加巴喷丁和血栓反应蛋白对新皮质损伤后增强兴奋性连通性、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连接的萌发、胶质细胞的变化和兴奋性突触的形成是脑损伤的后果，被认为是动物模型和人脑癫痫的原因。目前还没有有效的预防性治疗方法来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来限制皮层创伤后增加的兴奋性连接和癫痫的发展。星形胶质细胞分泌的血栓反应蛋白（tsp）在发育期间和皮层损伤后参与了新的兴奋性突触的形成。实验将验证普瑞巴林（PGB） （Lyrica）的假设，该药物是一种被批准的药物，可以干扰tsp与其α 2 δ -1受体的结合，从而减少兴奋性突触的形成和发芽，并限制癫痫样活动的发展。我们将在naïve小鼠、TSP“敲除”小鼠和alpha2delta-1过表达癫痫小鼠的部分皮质分离（“削弱”，UC）模型中探讨PGB和TSP对癫痫性新皮质损伤的影响。体外皮层记录癫痫样活动的发生率

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 naïve 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 naïve 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.