Motor cortex plasticity in temporal lobe epilepsy

颞叶癫痫的运动皮层可塑性

基本信息

批准号：
10531903
负责人：
Jaideep Kapur
金额：
$ 51.17万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-04-01 至 2025-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10531903
关键词：
AMPA Receptors Animal Model Animals Area Behavioral Biochemical Brain Cause of Death Cell Count Data Development Electroencephalography Electrophysiology (science)Epilepsy Estrogen Receptors Exhibits Experimental Models FDA approved FOS gene Fracture Fright Genetic Recombination Glutamates Hippocampus Image Immediate-Early Genes Injury Investigation Knockout Mice Lasers Long-Term Potentiation Maps Mediating Methods Microscope Modeling Molecular Monitor Motor Cortex Motor Skills Mus Neocortex Neurons Patients Pentylenetetrazole Persons Pharmaceutical Preparations Population Property Prosencephalon Proteins Refractory Reporter Research Risk Risk Factors Role Seizures Seminal Slice Soft Tissue Injuries Status Epilepticus Stimulus Structure Synapses Techniques Temporal Lobe Epilepsy Testing Tonic - clonic seizures conditional knockout dentate gyrus eighth grade experimental study hippocampal pyramidal neuron insight kainate knockout animal motor learning neocortical novel patch clamp postsynaptic promoter response skill acquisition sudden unexpected death in epilepsy therapeutic target third grade transmission process

项目摘要

Project summary Grand mal (great malady) seizures, now called generalized tonic clonic seizures (GTCS), are the most feared seizures because they can cause death and injury. Repeated GTCSs are the leading risk factor for sudden unexpected death in epilepsy (SUDEP), which is a leading cause of death in persons with epilepsy. GTCS also leads to fractures and soft tissue injuries. It is long known that the motor cortex generates these seizures and seizures modify the motor cortex. However, the cellular and molecular mechanisms of seizure-induced reorganization of the motor cortex have not been studied. Furthermore, it is not known whether a GTCS makes subsequent seizures more severe. We propose that GTCS enhance the excitability of a subset of motor cortex pyramidal neurons by enhancing AMPA receptor mediated excitation. We found that GluA1 subunit of the AMPA receptor was essential for expressing kindling-induced (grade 5) GTCS. We kindled mice lacking the GluA1 subunit of AMPA receptors and their wild-type (WT) littermates using traditional kindling methods. Whereas WT animals progressed to sustained convulsive GTCS (grade 4 & 5), but knockout animals neither attained nor sustained GTCS, despite repeated stimulation. Furthermore, two (WT) animals died following GTCS, while none of the KO animals died. In Aim 1, we propose to characterize the role of the GluA1 subunit of AMPA receptors in sustaining repeated GTCSs using a combination of conditional knockout mice and biochemical techniques in intrahippocampal kainate (IHK) and kindling models of TLE. Behavioral seizures also become more intense when fully kindled animals were stimulated. Much larger volume of the cortex was active during the 8th GTCS compared to the neocortical activation observed after the 3rd GTCS. Motor cortex cell counts revealed that many more neurons in the motor cortex expressed c-fos in response to the fifth GTCS compared to the first GTCS. In Aim 2 experiments, we propose to confirm and expand these findings. we will compare cortical circuit activity maps and behavioral seizures in response to the first or fifth GTCS in kindling and IHK TLE models. We compared the electrophysiological properties of motor cortex pyramidal neurons that expressed c-fos in response to GTCSs with those of surrounding neurons that did not express c-fos and found surprising differences. Motor cortex pyramidal neurons expressing c-fos were more excitable and demonstrated enhanced AMPA receptor-mediated excitatory post synaptic currents. In Aim 3, we propose to compare the excitability and excitatory transmission of layer 2/3 and layer 4/5 pyramidal neurons expressing c- fos in response to a grade 5 kindled seizure using patch clamp recordings. These studies open a novel area of epilepsy research, focusing on the effects of GTCS on the neocortex using a combination combine novel, state-of-the-art techniques.

项目概要大病（大病）癫痫发作，现在称为全身强直阵挛癫痫发作（GTCS），是最令人恐惧的癫痫发作，因为它们可能导致死亡和受伤。重复的 GTCS 是突发事件的主要风险因素癫痫意外死亡（SUDEP）是癫痫患者死亡的主要原因。 GTCS 还导致骨折和软组织损伤。众所周知，运动皮层会产生这些癫痫发作并癫痫发作会改变运动皮层。然而，癫痫诱发的细胞和分子机制运动皮层的重组尚未被研究。此外，尚不清楚 GTCS 是否使随后的癫痫发作更加严重。我们建议 GTCS 增强运动皮层子集的兴奋性锥体神经元通过增强 AMPA 受体介导的兴奋。我们发现 GluA1 亚基 AMPA 受体对于表达引火诱导的（5 级）GTCS 至关重要。我们点燃了缺乏使用传统点燃方法观察 AMPA 受体的 GluA1 亚基及其野生型 (WT) 同窝小鼠。 WT 动物进展为持续性惊厥 GTCS（4 级和 5 级），但基因敲除动物则没有尽管反复受到刺激，但仍无法达到或维持 GTCS。此外，两只（WT）动物死亡后 GTCS，而没有一只 KO 动物死亡。在目标 1 中，我们建议描述 GluA1 亚基的作用 AMPA 受体在维持重复 GTCS 中使用条件敲除小鼠和海马内红藻氨酸 (IHK) 的生化技术和 TLE 点燃模型。行为性癫痫发作当完全点燃的动物受到刺激时，也会变得更加强烈。皮质的体积要大得多与第 3 个 GTCS 后观察到的新皮质激活相比，第 8 个 GTCS 期间的激活。运动皮层细胞计数显示，运动皮层中有更多神经元表达 c-fos，以响应第五次 GTCS 与第一个 GTCS 相比。在目标 2 实验中，我们建议确认并扩展这些发现。我们将比较点燃中第一个或第五个 GTCS 的皮质回路活动图和行为癫痫发作和 IHK TLE 模型。我们比较了运动皮层锥体神经元的电生理特性与周围不表达 c-fos 的神经元一起表达 c-fos 以响应 GTCS，并发现令人惊讶的差异。表达 c-fos 的运动皮层锥体神经元更容易兴奋并且证明 AMPA 受体介导的兴奋性突触后电流增强。在目标 3 中，我们建议比较表达 c 的 2/3 层和 4/5 层锥体神经元的兴奋性和兴奋性传递- 使用膜片钳记录 fos 来响应 5 级点燃癫痫发作。这些研究开辟了一个新领域癫痫研究，重点关注 GTCS 使用新颖的组合对新皮质的影响，最先进的技术。