Mechanisms of interictal spike generation

发作间期尖峰产生的机制

• 批准号: 10222792
• 负责人: Kyle Patrick Lillis
• 金额: $ 38.71万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10222792
• 关键词: Acute; Animals; Antiepileptic Agents; Automobile Driving; Brain; Cells; Chlorides; Chronic; Custom; Data; Development; Devices; Electroencephalography; Elements; Epilepsy; Epileptogenesis; Generations; Goals; Hippocampus (Brain); Human; Image; In Vitro; Incubators; Individual; Injections; Interneurons; Kainic Acid; Label; Light; Link; Microscope; Modeling; Molecular; Mus; Neurons; Optics; Output; Pathologic; Pathway interactions; Patients; Pattern; Phase; Phenotype; Population; Preparation; Proteins; Publishing; Resolution; Role; Sampling; Seizures; Slice; Synapses; System; Temporal Lobe Epilepsy; Testing; Unconscious State; awake; base; behavioral phenotyping; calcium indicator; cell type; design; digital; experimental study; gamma-Aminobutyric Acid; in vivo; in vivo imaging; innovation; insight; kainate; microendoscopy; neural network; novel; novel therapeutics; optogenetics; response; tissue culture

Epilepsy is characterized by two pathological electrographic phenotypes: seizures and interictal spikes. Seizures are relatively rare sustained elevations in brain activity or synchronization that often produce a loss of consciousness in patients suffering from epilepsy. Interictal spikes are much more frequent (on the order of 1 per minute), brief (~200ms), and have no behavioral phenotype (patient is typically not aware of interictal spikes). It is well-established that epileptic networks commonly generate both types of discharge and mounting evidence suggests that there is a direct link between interictal spikes and seizure onset. This proposal aims to dissect the basic mechanisms of interictal spike generation, which will offer new insight into the dynamics of epileptic neural networks (and, in turn, inform development of novel therapeutics). The proposed project will investigate the origins of interictal spikes using an experimentally accessible preparation, the organotypic slice culture (which spontaneously develops interictal spikes and seizures during its first weeks in culture), and a custom microscope (the “Incuscope”) specially designed to record and manipulate activity with single-cell resolution, across the entire epileptic network. Imaging the entire epileptic network guarantees that epileptiform activity observed is not driven by external input. Furthermore, the Incuscope is built inside of a tissue culture incubator, enabling continuous, month-long imaging as epileptic activity emerges and evolves. Findings will be validated in intact animals using endomicroscopy-based in vivo imaging of interictal spikes. The primary goals of this project are as follows: 1) Identify subpopulations of early-firing cells during interictal spikes. 2) Optically stimulate early-firing cells to characterize the degree to which their activation is sufficient to initiate spikes. 3) Optically inhibit early-firing cells to characterize the degree to which their activation is necessary to initiate spikes. 4) Repeat experiments 1-3 in long-term (multi- week) recordings to characterize the stability of early-firing cells and correlate observed changes with seizure onset and seizure burden. 5) Repeat experiment 1 in awake mice, using endomicroscopy and the intrahippocampal kainate model of epilepsy, to test whether the same population of cells is involved in generating interictal spikes in vivo.

癫痫的特征是两种病理电学表型：癫痫发作和充线峰。 癫痫发作是相对较少的脑活动或同步的持续升高，通常会产生 患有癫痫患者的意识丧失。充 每分钟1），简短（〜200ms），没有行为表型（患者通常不是 意识到发作尖峰）。众所周知的是，癫痫网络通常会生成两种类型 排放和安装的证据表明，间孔隙之间存在直接联系 癫痫发作。该提案旨在剖析间峰产生的基本机制，这是 将为癫痫神经元网络的动态提供新的见解 新疗法）。 拟议的项目将使用实验可访问的发作尖峰的起源 准备，有机切片培养物（在赞助上发展发作尖峰和癫痫发作 在文化的最初几周内），以及专门设计的定制显微镜（“ incuscope”） 在整个癫痫网络中，通过单细胞分辨率记录和操纵活动。成像 整个癫痫网络保证观察到的癫痫样活动不会由外部驱动 输入。此外，障碍物是在组织培养孵化器内部建造的，使得连续， 随着癫痫活性的出现和演变，长达一个月的成像。发现将在完整动物中得到验证 使用基于iNMROSCOPY的间体尖峰的体内成像。 该项目的主要目标如下：1）确定在 间歇性尖峰。 2）光学刺激早期射击细胞以表征其其程度 激活足以引发峰值。 3）光学抑制早期发射细胞以表征该度 它们的激活是启动峰值所必需的。 4）长期重复实验1-3 每周）记录以表征早期射击细胞的稳定性，并将观察到的变化与 癫痫发作和癫痫发作负担。 5）在清醒小鼠中重复实验1，使用巨型显体和 癫痫的乳腺内海事内海藻酸盐模型，以测试是否参与相同的细胞群 在体内产生间歇性尖峰。