Brain Wide Anesthetic-Active Neuronal Network

全脑麻醉活性神经元网络

• 批准号: 10712033
• 负责人: Max Kelz
• 金额: $ 55.78万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10712033
• 关键词: 3-Dimensional; Affinity; Anatomy; Anesthesia procedures; Anesthesiology; Anesthetics; Area; Arousal; Behavior assessment; Behavioral; Bioinformatics; Biological; Biological Process; Brain; Brain imaging; Brain region; Caring; Cell Nucleus; Cells; Conscious; Cre driver; Development; Disease; Drug Design; Drug Interactions; Elements; FOS gene; Fiber; Future; General Anesthesia; General anesthetic drugs; Genetic; Goals; Health; Hypnosis; Hypothalamic structure; Immunohistochemistry; Individual; Intervention; Knowledge; Label; Life; Maps; Molecular; Molecular Target; Monitor; Mus; Nervous System; Neurons; Operative Surgical Procedures; Optics; Partner in relationship; Patients; Pattern; Photometry; Physiological; Play; Population; Prefrontal Cortex; Procedures; Property; Reporter; Research; Resolution; Role; Site; Source; Techniques; Thalamic structure; Time; Tissues; Transfection; Transgenic Mice; Transgenic Organisms; Unconscious State; Viral; Virus; Work; analysis pipeline; cell type; clinically significant; connectome; density; designer receptors exclusively activated by designer drugs; druggable target; experience; hypnotic; immunoreactivity; improved; in vivo; innovation; interest; neural circuit; neuronal circuitry; neurophysiology; novel; optogenetics; pharmacologic; rational design; two photon microscopy

Abstract Anesthetics are low affinity drugs that interact with hundreds of molecular targets present throughout the nervous system at clinically significant concentrations. Despite this molecular-level promiscuity, the hypnotic effects of anesthetics depend critically on specific neural circuits. This assertion is supported by numerous results showing that direct modulation of specific sites distributed broadly throughout the brain can potentiate or, conversely, antagonize the anesthetic state. However, because previous experimental work focused upon one brain site at a time, the identification of the long-hypothesized brain-wide canonical anesthesia circuit has so far remained elusive. To fill this critical gap in knowledge, we reasoned that ultimately, the state of anesthesia must be imposed onto the brain by neurons that remain active under anesthesia, while most other neurons are suppressed. To identify anesthetic active neurons throughout the brain, we used tissue clearing and 3D c-Fos immunohistochemistry. We validated that putative anesthesia-active neurons are indeed physiologically active in vivo using two photon microscopy and fiber photometry. Having identified anesthesia- active neurons, we further reasoned that brain regions which project broadly are more likely to play a pivotal role in modulating the level of consciousness. Thus, we combined our brain activity map with whole brain connectivity analyses. The potent combination of these experimental and bioinformatics approaches allowed us to identify regions that contain a high density of anesthetic-active neurons and project broadly throughout the brain. Our unbiased approach culminated in the definition of a putative canonical anesthesia network comprised of nuclei in the ventral hypothalamus, thalamus, and the prefrontal cortex. In Aim 1, we will discover the specific cell types within prefrontal cortex, ventral hypothalamus and thalamus that remain active under anesthesia. This is of critical importance as all brain regions contain many cell subtypes with distinct neurophysiological properties, connectivity patterns, and ultimately, behavioral effects. In Aim 2, we will discover the brain-wide projections made by anesthetic-active neurons by combining anterograde and retrograde viral tracing in transgenic mice that specifically label distinct neuronal subtypes with 3D immunohistochemistry. In Aim 3, we will establish the functional roles of the canonical anesthesia network as a whole and each of its elements individually by combining chemo- and optogenetics with behavioral and neurophysiologic assessments of arousal. The ultimate result of the proposed research will be the identification of a canonical network of neurons sufficient to elicit hypnosis. This has fundamental implications for how the state of arousal is controlled in health and dysregulated in disease. Identification of this circuit may also suggest druggable targets for the development of more specific anesthetic agents with fewer undesirable effects. This has the potential to significantly improve the care of millions of patients requiring general anesthesia for life saving procedures.

摘要 麻醉药是一种低亲和力的药物，它与数百个分子靶点相互作用。 神经系统在临床上有显著浓度。尽管有这种分子水平的乱交，催眠药 麻醉药的作用很大程度上取决于特定的神经回路。这一断言得到了许多人的支持 结果表明，直接调节大脑中广泛分布的特定部位可以增强 或者，相反，对抗麻醉状态。然而，由于之前的实验工作主要集中在 一次识别一个大脑部位，识别长期假想的全脑经典麻醉回路 到目前为止，人们仍然难以捉摸。为了填补这一关键的知识空白，我们推断，最终， 麻醉必须由在麻醉下保持活跃的神经元强加给大脑，而大多数其他 神经元受到抑制。为了识别整个大脑的麻醉活性神经元，我们使用了组织清除法 3Dc-Fos免疫组织化学染色。我们证实了假定的麻醉活性神经元确实是 利用双光子显微镜和纤维光度法进行体内生理活性测定。在确定了麻醉方法后- 对于活跃的神经元，我们进一步推断，大脑中广泛投射的区域更有可能发挥关键作用 在调节意识水平方面的作用。因此，我们将我们的大脑活动图与整个大脑相结合 连通性分析。这些实验和生物信息学方法的有效结合允许 US识别包含高密度麻醉活性神经元的区域并广泛投射到 大脑。我们不偏不倚的方法最终定义了一个假定的规范麻醉网络 由下丘脑腹侧、丘脑和前额叶皮质的核组成。在目标1中，我们将发现 前额叶皮质、下丘脑腹侧和丘脑内保持活跃的特定细胞类型 麻醉。这一点至关重要，因为所有大脑区域都包含许多不同的细胞亚型 神经生理特性、连通性模式以及最终的行为效应。在目标2中，我们将 通过将顺行和顺行相结合，发现麻醉活性神经元所做的全脑投射 用3D特异性标记不同神经元亚型的转基因小鼠的逆行病毒追踪 免疫组织化学。在目标3中，我们将确立规范麻醉网络作为 通过将化学和光遗传学与行为和光遗传学相结合 觉醒的神经生理学评估。拟议研究的最终结果将是确定 一个足以引发催眠的神经元的规范网络。这具有根本性的含义，即 唤醒状态在健康时是受控的，在疾病中是失控的。该电路的标识还可以 建议以更少的不良反应开发更具体的麻醉剂的可药物靶点 效果。这有可能显著改善数百万需要一般护理的患者的护理 用于救生程序的麻醉。