Photoacoustic Microscopy of the Awake Mouse Brain

清醒小鼠大脑的光声显微镜

• 批准号: 10106311
• 负责人: Song Hu
• 金额: $ 19.59万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-14 至 2022-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10106311
• 关键词: Photoacoustic; Microscopy; Awake; Mouse; Brain

PROJECT SUMMARY A long-standing technical challenge in neuroscience is high-resolution functional and molecular imaging of the awake mouse brain. The need is evident and pressing, because anesthesia can significantly reduce the overall brain activity and alter multiple forms of brain dynamics. The profound effects of anesthesia may confound the readouts of conventional microscopies, which require preparations of anesthetized animals, and thus impose significant limitations on the interpretation and translation of basic neuroscience findings. Moreover, incapable of imaging the awake brain for direct comparison with the anesthetized counterpart, conventional microscopies are of very limited utility in examining the important yet elusive roles of general anesthesia in the progression of multiple life-threatening brain disorders (e.g., ischemic stroke and Alzheimer's disease, which are the leading causes of death and disability in the United States). In addressing this challenge, recent efforts have extended the scope of fluorescence microscopy to the awake brain. While this molecular imaging technology advances and rapidly expands our understanding of the neural activities underlying behavior, high-resolution functional imaging of the coevolving hemodynamics falls far behind. This project aims to bridge the increasing technology gap by developing a first-of-a-kind photoacoustic microscopy (PAM) instrumentation for functional imaging of cerebral hemodynamics and metabolism at high spatiotemporal resolution in awake mice. The unprecedented speed of the proposed awake-brain PAM (1 MHz A-line rate), enabled by the innovative designs of wide-field optical-mechanical hybrid scan and MHz-repetition-rate dual-wavelength Raman laser, will exceed that of the existing multi-parametric PAM by two orders of magnitude and will enable spatiotemporal visualization of the functional and metabolic responses of the brain to neural stimulations and disease onsets without the influence of anesthesia. The complementary algorithms for statistical, spectral and correlation analysis of the same PAM dataset will further push the technology envelope by enabling simultaneous and comprehensive quantification of the total concentration and oxygen saturation of hemoglobin, blood flow and perfusion, and metabolic supply and demand at the microscopic level. This technology innovation will open up new and exciting opportunities in basic and translational neuroscience, including the mechanistic study of anesthetic neuroprotection in ischemic stroke proposed in this project. In turn, this stroke study will provide an ideal setting to assess the potential of awake-brain MHz-PAM in the context of a clinically important brain disease and pave the way for future studies of neurovascular coupling and neuromodulation in the awake brain. These efforts, together, hold the potential to establish PAM as a new enabling technology in brain research.

项目概要 神经科学中长期存在的技术挑战是高分辨率功能和分子成像 清醒的老鼠大脑。这种需求是显而易见且紧迫的，因为麻醉可以显着降低总体 大脑活动并改变多种形式的大脑动力学。麻醉的深远影响可能会令 传统显微镜的读数需要麻醉动物的准备，因此强加 对基本神经科学发现的解释和翻译存在重大限制。而且，无能为力 对清醒大脑进行成像，以便与麻醉状态下的大脑、传统显微镜直接进行比较 在检查全身麻醉在疾病进展中的重要但难以捉摸的作用方面作用非常有限 多种危及生命的脑部疾病（例如缺血性中风和阿尔茨海默氏病，这是主要的 美国死亡和残疾的原因）。为了应对这一挑战，最近的努力已扩大 荧光显微镜的范围扩大到清醒的大脑。虽然分子成像技术不断进步 并迅速扩展我们对行为背后的神经活动的理解，高分辨率功能 共同演化血流动力学的成像远远落后。该项目旨在架起日益增长的技术桥梁 通过开发首创的用于功能成像的光声显微镜 (PAM) 仪器来填补这一空白 清醒小鼠的高时空分辨率脑血流动力学和代谢。史无前例的 所提出的清醒大脑 PAM 的速度（1 MHz A 线速率），由宽视场的创新设计实现 光机混合扫描和MHz重复率双波长拉曼激光器，将超越 现有的多参数 PAM 提高了两个数量级，并将实现时空可视化 大脑对神经刺激和疾病发作的功能和代谢反应而不受影响 麻醉。同一 PAM 的统计、频谱和相关分析的互补算法 数据集将通过实现同步和全面的量化来进一步推动技术极限 血红蛋白总浓度和氧饱和度、血流量和灌注以及代谢供应 以及微观层面的需求。这项技术创新将开辟新的、令人兴奋的机会 基础和转化神经科学，包括缺血性麻醉神经保护的机制研究 本项目中提出的中风。反过来，这项中风研究将为评估中风的潜力提供一个理想的环境。 清醒大脑 MHz-PAM 在临床上重要的脑部疾病中的应用，为未来的研究铺平道路 清醒大脑中的神经血管耦合和神经调节。这些努力共同发挥着潜力 将 PAM 确立为大脑研究的新支持技术。