In Vivo Analysis of Cortical Projection Neurons

皮质投射神经元的体内分析

• 批准号: 8816156
• 负责人: Gordon M Shepherd
• 金额: $ 19.31万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8816156
• 关键词: Address; Amyotrophic Lateral Sclerosis; Animal Model; Animals; Area; Autistic Disorder; Axon; Behavior; Behavior Control; Behavioral Paradigm; Brain; Calcium; Cells; Cognitive; Complex; Corpus striatum structure; Data; Dendrites; Disease; Fiber Optics; Future; Goals; Health; Human; Huntington Disease; Image; Investigation; Knowledge; Learning; Link; Measures; Methods; Mission; Monitor; Motor; Motor Cortex; Movement; Multiple Sclerosis; Mus; National Institute of Neurological Disorders and Stroke; Neocortex; Neuraxis; Neurologic; Neurons; Output; Paralysed; Parkinson Disease; Pathology; Pattern; Pharmacogenetics; Photometry; Population; Process; Property; Public Health; Rabies virus; Recombinants; Reporter; Research; Resolution; Role; Signal Transduction; Slice; Spinal Cord; Spinal cord injury; Stroke; Synapses; Time; United States National Institutes of Health; Viral; Viral Vector; Whole-Cell Recordings; awake; base; calcium indicator; cell type; clinically relevant; disability; hippocampal pyramidal neuron; improved; in vivo; innovation; insight; interest; mental function; mouse model; neocortical; nervous system disorder; neuropsychiatry; novel strategies; optical fiber; optogenetics; programs; relating to nervous system; research study; temporal measurement; tool; two-photon

DESCRIPTION (provided by applicant): An essential aspect of human behavior is the ability to perform skilled and purposive movements. This ability relies on an intact neocortex, and in particular on different classes of projection neurons that convey neural information from the neocortex to downstream circuits involved in behavior. Two classes of cortical projection neurons are of particular interest - corticospinal neurons, projecting to the spinal cord, and corticostriatal neurons, projecting to the striatum bilaterally. While much has been learned from brain slice experiments about the cellular and synaptic properties of corticospinal and corticostriatal neurons, knowledge about their activity patterns in vivo in relation to volitional movements has been impeded due to a lack of easy to use methods for selectively recording from and manipulating the activity of these projection neurons. Here, building on prior ex vivo experiments, we propose a research program to develop new approaches to address this gap. In one aim, we will develop multiple complementary approaches to record the activities of corticospinal and corticostriatal neurons in the awake, moving mouse. In one set of studies we will use in vivo whole-cell recordings to record from motor cortex neurons at high sensitivity and temporal resolution, with post-hoc identification of cell types. In parallel studies we will infect corticospinal and corticostriatal neurons with recombinant rabies viruses carrying genetically encoded calcium indicators (GECIs), and detect activity either at high resolution using two- photon calcium imaging or at a population level using optical fibers. In our second aim, we will develop methods to manipulate the activities of corticospinal and corticostriatal neurons in the awake, moving mice. By either up- or down-regulate projection neuron activity using optogenetic or pharmacogenetic tools, we will be able to begin to address the question of how corticospinal and corticostriatal neurons' activities are causally related to movement parameters. The proposed research program is innovative and significant, we believe, because it will generate multiple new experimental paradigms for probing the in vivo functions of cortical projection neurons, not only in motor areas but across all of neocortex, and because these tools will be readily applicable to mouse models of neurological disease.

描述（由申请人提供）：人类行为的一个重要方面是执行熟练且有目的的动作的能力。这种能力依赖于完整的新皮质，特别是不同类别的投射神经元，它们将神经信息从新皮质传递到参与行为的下游回路。两类皮质投射神经元特别令人感兴趣——皮质脊髓神经元，投射到脊髓，皮质纹状体神经元，投射到双侧纹状体。虽然从脑切片实验中已经了解到很多关于皮质脊髓和皮质纹状体神经元的细胞和突触特性的信息，但由于缺乏选择性记录和操纵这些投射神经元活动的易于使用的方法，对它们与意志运动相关的体内活动模式的了解受到了阻碍。在此，基于先前的离体实验，我们提出了一项研究计划，以开发新方法来解决这一差距。目标之一是，我们将开发多种互补方法来记录清醒、运动小鼠的皮质脊髓和皮质纹状体神经元的活动。在一组研究中，我们将使用体内全细胞记录以高灵敏度和时间分辨率记录运动皮层神经元，并事后识别细胞类型。在平行研究中，我们将感染 使用携带基因编码钙指示剂（GECI）的重组狂犬病病毒检测皮质脊髓和皮质纹状体神经元，并使用双光子钙成像在高分辨率下或使用光纤在群体水平上检测活动。我们的第二个目标是开发方法来操纵清醒、运动小鼠的皮质脊髓和皮质纹状体神经元的活动。通过使用光遗传学或药物遗传学工具上调或下调投射神经元活动，我们将能够开始解决皮质脊髓和皮质纹状体神经元的活动如何与运动参数因果关系的问题。我们相信，拟议的研究计划是创新且意义重大的，因为它将产生多种新的实验范式，用于探测皮层投射神经元的体内功能，不仅在运动区域，而且在整个新皮层，并且因为这些工具将很容易适用于神经系统疾病的小鼠模型。