Novel method to quantify conditioned fear-based neuronal activity in rat brain in vivo using high-resolution photoacoustic imaging

使用高分辨率光声成像量化大鼠大脑体内基于条件恐惧的神经元活动的新方法

• 批准号: 10437819
• 负责人: James Matchynski
• 金额: $ 5.43万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-06 至 2024-07-05
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10437819
• 关键词: Address; Amygdaloid structure; Animal Model; Anterior; Area; Attenuated; Behavior; Behavioral; Behavioral Model; Behavioral Research; Blood; Brain; Brain region; Cells; Cerebrum; Chemicals; Chromogenic Substrates; Complex; Conditioned Stimulus; Contrast Media; Coupled; Data; Detection; Development; Disease; Dorsal; Dyes; Engineering; Experimental Designs; Exposure to; FOS Protein; FOS gene; Failure; Female; Fright; Functional Magnetic Resonance Imaging; Generations; Goals; Hand; Hemoglobin; Hippocampus (Brain); Home; Human; Image; Imaging Techniques; Immediate-Early Genes; Immunofluorescence Immunologic; Impairment; Knowledge; Label; LacZ Genes; Lasers; Learning; Light; Maps; Measurement; Measures; Medial; Mediating; Mental disorders; Methodology; Methods; Microscopy; Modeling; Molecular; Neurons; Neurosciences; Noise; Oxygen; Physicians; Physics; Physiologic pulse; Pilot Projects; Positioning Attribute; Post-Traumatic Stress Disorders; Prefrontal Cortex; Prevalence; Process; Rattus; Reporter Genes; Resolution; Rodent; Role; Science; Scientist; Shock; Signal Transduction; Slice; Specificity; Techniques; Technology; Testing; Time; Tissues; Training; Transgenic Organisms; Ultrasonic wave; Validation; absorption; addiction; base; behavioral response; behavioral study; beta-Galactosidase; career; chromophore; cingulate cortex; classical conditioning; conditioned fear; cost; disabling symptom; effective intervention; high resolution imaging; image reconstruction; imaging approach; imaging capabilities; imaging modality; imaging system; in vivo; in vivo imaging; indigo dye; innovation; insight; longitudinal analysis; male; member; nervous system disorder; neural circuit; neuroimaging; novel; photoacoustic imaging; portability; protein expression; response; serial imaging; targeted treatment; temporal measurement; theories; therapy development

Project Summary/Abstract Mental health disorders, such as post-traumatic stress disorder (PTSD), are complex, leaving challenges for the development of effective interventions. Increasing our detailed understanding of these disorders, by studying the micro-neurocircuitry behind them, can help provide individualized solutions to these complicated conditions. This micro-neurocircuitry can be investigated by studying small groups of highly-active neurons, collectively known as neuronal ensembles, that are responsible for unique behavioral responses, e.g. fear learning, in PTSD. Behavioral studies examining neuronal ensembles have thus far been largely ex vivo, using immediate early genes associated with neuronal activity (e.g. c-Fos). In vivo imaging methods are currently limited (very invasive or low resolution), and generally measure indirect neuronal activity, such as the blood oxygen dependent response. To address this knowledge gap, we propose a new high-resolution imaging approach to detect and quantify fear-related neuronal activity in vivo, with the goal of discovering more detailed roles of the neuronal ensembles that mediate fear learning associated with PTSD. Specifically, we propose using photoacoustic (PA) imaging to map activated neurons in a Fos/LacZ transgenic rat model. Fusion of Fos, which is induced by neuronal activity, with the lacZ gene gives active (Fos+) cells the ability to cleave pro-chromogenic substrates, such as X-Gal, enzymatically, into PA active dyes. My phantom and ex vivo pilot studies in rat brains demonstrate high-contrast PA images using these dyes and image reconstructions with a very high signal-to-noise ratio. We hypothesize that during fear acquisition, unique neuronal ensembles will be activated and detectable in the medial prefrontal cortex (a region tightly associated with fear behavior) using a novel Fos/LacZ PA imaging system, providing a means to track longitudinal changes in these ensembles in vivo. To test this hypothesis, we will use male/female Fos/LacZ transgenic rats that will be administered cortical X-Gal upon exposure to footshock (fear). The X-Gal product will be PA imaged (Aim 1) and these images will be validated with traditional methods for immunohistochemical detection of Fos and β-galactosidase in brain slices (Aim 2). Significance: This project will provide deeper insight into the role of fear-related neuronal ensembles and provide a new, low cost, high-resolution methodological approach to measure Fos expression longitudinally (representative of neuronal ensembles) in vivo. This will be broadly useful for behavioral research, not only in PTSD, but also in a variety of psychiatric science by allowing us to better define mechanisms behind complex mental health disorders. My training will focus on three main areas: molecular neuroscience and microscopy (led by sponsor, Dr. Conti), behavioral/animal modeling (led by co-sponsor, Dr. Perrine), and use of PA imaging (led by key training team member, Dr. Avanaki), facilitating my path towards my neuroradiology physician-scientist career goal.

项目总结/摘要 心理健康障碍，如创伤后应激障碍（PTSD），是复杂的，留下的挑战， 制定有效的干预措施。增加我们对这些疾病的详细了解， 研究它们背后的微观神经回路，可以帮助为这些复杂的问题提供个性化的解决方案。 条件这种微神经回路可以通过研究一小群高度活跃的神经元来研究， 统称为神经元集合，负责独特的行为反应，例如恐惧 在创伤后应激障碍中学习迄今为止，检查神经元集合的行为研究主要是离体的，使用 与神经元活动相关的立即早期基因（例如c-Fos）。体内成像方法目前 有限（侵入性很强或分辨率低），通常测量间接神经元活动，例如血液 氧依赖性反应为了解决这一知识缺口，我们提出了一种新的高分辨率成像方法， 一种检测和量化体内恐惧相关神经元活动的方法，目的是发现更多 详细的作用，神经元合奏，介导恐惧学习与创伤后应激障碍。 具体来说，我们建议使用光声（PA）成像来映射Fos/LacZ中的激活神经元。 转基因大鼠模型。由神经元活性诱导的Fos与lacZ基因的融合产生活性（Fos+） 细胞酶促裂解前显色底物如X-Gal为PA活性染料的能力。我 在大鼠脑中的模型和离体试验研究证明了使用这些染料和成像的高对比度PA图像 具有非常高的信噪比的重建。我们假设，在获得恐惧的过程中， 在内侧前额叶皮层（一个紧密结合的区域）中，神经元集合将被激活并被检测到。 与恐惧行为相关），使用新型Fos/LacZ PA成像系统，提供了一种跟踪 在体内这些集合的纵向变化。为了验证这一假设，我们将使用男性/女性Fos/LacZ 将在暴露于足电击（恐惧）后施用皮质X-Gal的转基因大鼠。X-Gal产品将 PA成像（目标1），这些图像将用传统的免疫组织化学方法进行验证 检测脑片中Fos和β-半乳糖苷酶（目的2）。意义：该项目将提供更深层次的 深入了解恐惧相关神经元集合的作用，并提供一个新的，低成本，高分辨率 方法学方法来测量Fos表达纵向（代表神经元集合）， vivo.这将是广泛有用的行为研究，不仅在创伤后应激障碍，而且在各种精神病 让我们更好地定义复杂的心理健康障碍背后的机制。 我的培训将集中在三个主要领域：分子神经科学和显微镜（由赞助商，博士领导。 Conti）、行为/动物建模（由共同申办者Perrine博士领导）和PA成像的使用（由关键培训领导 团队成员Avanaki博士），促进我实现神经放射学医生-科学家职业目标的道路。