Non-invasive Chemical Genetic Control of Neuronal Activity

神经元活动的非侵入性化学遗传控制

• 批准号: 7885367
• 负责人: MICHAEL D EHLERS
• 金额: $ 38.61万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7885367
• 关键词: Action Potentials; Acute; Afferent Neurons; Agonist; Animals; Area; Autistic Disorder; Behavior; Behavioral; Blood - brain barrier anatomy; Brain; Cannulas; Capsaicin; Cells; Charge; Data; Development; Dopamine; Dose; Engineering; Epilepsy; FOS gene; Fluorescent Dyes; Gated Ion Channel; Genetic; Glutamates; Goals; Implant; Infusion procedures; Injection of therapeutic agent; Knock-in Mouse; Laboratories; Lidocaine; Ligands; Maps; Membrane; Memory; Mental Depression; Mental disorders; Metabolic; Metabolism; Methods; Microdialysis; Modeling; Monitor; Mus; Neurologic; Neurons; Neurosciences; Nociception; Operative Surgical Procedures; Optics; Peripheral; Pharmaceutical Preparations; Physiological; Population; Public Health; Purkinje Cells; Reading; Regulation; Research; Resiniferatoxin; Response Latencies; Route; Schizophrenia; Slice; Sodium Channel; Sodium Channel Blockers; Specificity; Staining method; Stains; Stereotyped Behavior; System; TRPV1 gene; Techniques; Technology; Testing; Therapeutic; Time; Work; addiction; awake; base; behavior influence; brain cell; cell type; chemical genetics; direct application; dopaminergic neuron; implantation; in vivo; interest; light gated; mouse model; neural circuit; neural stimulation; new technology; novel; programs; public health relevance; public health research; receptor; relating to nervous system; research study; response; sensory stimulus; small molecule; technology development

DESCRIPTION (provided by applicant): Mapping functional circuits is a major goal for both cellular and systems neuroscience. Current approaches for mapping neural circuits are limited by the lack of technologies for evoking cell-specific neural activity. Available methods of neural stimulation rely on either local application of undiscriminating fields of electrical currents, glutamate uncaging, or the presentation of artificial sensory stimuli. Although recent use of light- gated ion channels has provided optical control of neuronal activity on rapid time scales, such approaches are limited by the requirement for direct optical access to neuronal populations of interest, and are not currently suitable for activating large brain areas or disperse neuronal populations. A transformative technology for neuroscience would be non-invasive control over neural activity in genetically defined populations of neurons in the mammalian brain. Such a goal requires combining genetic sensitization of neuronal subsets with a means to manipulate their electrical activity remotely without surgery or intracranial implants. To create such a technology, my laboratory has initiated a program of in vivo chemical genetic and physiological studies to engineer a mouse model suitable for precise non-invasive manipulation of neural activity in genetically defined populations of neurons in vivo. We have developed a conditional mouse model that sensitizes genetically defined neurons to an artificial ligand (capsaicin) by cell type-specific expression of a heterologous receptor (TRPV1). We have found that application of capsaicin to neurons expressing TRPV1 induces strong inward currents, triggers robust firing of action potentials, and activates stereotyped behaviors. Taking advantage of these preliminary data, and the extensive pharmacological and biophysical characterization of TRPV1, we propose to extend and modify this model to enable peripheral administration of agonists for central activation of defined neuronal subsets. Moreover, because the large TRPV1 channel pore is permeable to small molecules, including the membrane-impermeant sodium channel blocker QX-314, we propose to test this novel mouse model to enable both activation and inhibition of neuronal activity. This work will allow for the development of a novel in vivo technology for chemical genetic regulation of neuronal activity that is (1) orthogonal to optical and optogenetic strategies, (2) based on the only current Cre/lox-based model for neuronal activation, (3) may allow for fully non-invasive CNS activation by drug injection, and (4) may enable targeted small molecule delivery to defined neuronal subsets. PUBLIC HEALTH RELEVANCE: The proposed research will develop a novel technology for non-invasive control over electrical activity in genetically defined populations of brain cells. Abnormal electrical activity in the brain contributes to epilepsy, memory decline, depression, autism, schizophrenia, and addiction. By developing a crucial new technology for targeted manipulation of brain cell activity and metabolism, the proposed research will define novel brain circuits and therapeutic strategies for treating these devastating neurological and psychiatric disorders, which currently have a profound negative impact on public health.

描述（由申请人提供）：映射功能电路是细胞和系统神经科学的主要目标。目前用于映射神经回路的方法受到缺乏用于唤起细胞特异性神经活动的技术的限制。现有的神经刺激方法依赖于局部应用无差别的电流场、谷氨酸释放或人工感觉刺激的呈现。尽管最近使用光门控离子通道已经提供了在快速时间尺度上对神经元活动的光学控制，但是这种方法受到直接光学接近感兴趣的神经元群体的要求的限制，并且目前不适合于激活大的脑区域或分散的神经元群体。神经科学的一项变革性技术将是对哺乳动物大脑中遗传定义的神经元群体的神经活动进行非侵入性控制。这样的目标需要将神经元亚群的遗传致敏与远程操纵其电活动的手段相结合，而无需手术或颅内植入物。为了创造这样一种技术，我的实验室已经启动了一项体内化学遗传学和生理学研究计划，以设计一种小鼠模型，该模型适用于精确的非侵入性操纵体内遗传定义的神经元群体中的神经活动。我们已经开发了一种条件性小鼠模型，通过异源受体（TRPV 1）的细胞类型特异性表达，使遗传上定义的神经元对人工配体（辣椒素）敏感。我们发现，辣椒素对表达TRPV 1的神经元的应用诱导了强烈的内向电流，触发了动作电位的强烈放电，并激活了刻板行为。利用这些初步的数据，以及广泛的药理学和生物物理学特性的TRPV 1，我们建议扩展和修改这个模型，使周边管理的激动剂的中央激活的定义的神经元子集。此外，由于大的TRPV 1通道孔是可渗透的小分子，包括膜不渗透性钠通道阻滞剂QX-314，我们建议测试这种新的小鼠模型，使激活和抑制神经元活动。这项工作将允许开发一种用于神经元活性的化学遗传调节的新型体内技术，其（1）与光学和光遗传学策略正交，（2）基于目前唯一的基于Cre/lox的神经元活化模型，（3）可以允许通过药物注射进行完全非侵入性CNS活化，以及（4）可以实现靶向小分子递送至定义的神经元亚群。公共卫生关系：这项拟议中的研究将开发一种新技术，用于非侵入性地控制遗传定义的脑细胞群体的电活动。大脑中异常的电活动会导致癫痫、记忆力下降、抑郁、自闭症、精神分裂症和成瘾。通过开发一种针对脑细胞活动和代谢的关键新技术，拟议的研究将定义新的脑回路和治疗策略，用于治疗这些破坏性的神经和精神疾病，这些疾病目前对公共卫生产生了深远的负面影响。