Identifying cellular mechanisms underlying abnormal repetitive behaviors using in vivo microscopy

 描述（由申请人提供）：强迫症（OCD）的特征是侵入性思维和强迫性行为，这些行为减少了由这些强迫性思维产生的焦虑。了解这种疾病的病理和分子特征仍然是神经精神病学研究的一个相当大的挑战。本研究的目的是探讨神经回路中大规模神经活动模式的变化如何导致异常强迫行为，以及异常强迫行为的解决。长期以来的理论表明，异常的重复行为是由直接和间接纹状体通路的不平衡以及眶额皮质（OFC）活动增加引起的。然而，直到最近才能验证这一理论。最新的头戴式体内显微镜使我们能够同时观察清醒小鼠脑深部结构中数百个神经元中的Ca 2+信号。使用这种成像技术结合特定回路操作工具，我们可以开始测试OFC，直接和间接纹状体通路。为了研究神经活动如何随着持续行为而演变，我们将观察眶额皮层及其腹内侧纹状体（VMS）中的靶点的活动。这些区域是靶向的，因为它们在MRI研究中显示出结构和功能异常。钙活性将在OFC或VMS中可视化，具有D1或D2特异性。我们将比较异常重复行为小鼠的神经元活动，以研究D1+和D2+纹状体活动模式与持续行为之间的关系。然后可以分析纵向数据集，以了解网络活动的变化以及与数小时、数周或数月内行为的联系。将使用三种不同的方法（药理学、转基因和光遗传学）和时间尺度研究与行为相关的OFC和VMS D1/D2细胞活性。1)小鼠将接受药理学试剂注射以诱导短暂的持续行为。2)SAPAP 3基因敲除小鼠（一种转基因强迫症模型）将随着持续行为的发展而进行纵向研究。3)OFC-VMS投射将被光遗传学刺激，以在刺激之前、期间和之后用钙成像诱导持续行为数周。

 DESCRIPTION (provided by applicant): Obsessive compulsive disorder (OCD) is characterized by intrusive thoughts and compulsive behaviors that reduce the anxiety generated by these obsessions. Understanding the pathological and molecular features of this disorder remains a considerable challenge in neuropsychiatry research. The goal of this research is to investigate how changes in large-scale neural activity patterns in neural circuits occur leading to, during, and the resolution of abnormal compulsive behaviors. Longstanding theory indicates that abnormal repetitive behaviors result from imbalances in the direct and indirect striatal pathways as well as increased orbitofrontal cortex (OFC) activity. However, until recently it was not possible to test this theory. Newly available head mounted in vivo microscopes allow us to simultaneously visualize Ca2+ signaling in hundreds of neurons within deep brain structures in awake-behaving mice. Using this imaging technology in combination with tools for circuit-specific manipulation, we can begin to test the OFC, the direct, and indirect striatal pathways. To examine how neural activity evolves with perseverative behavior we will visualize activity in the OFC and its targets in the ventromedial striatum (VMS). These areas are targeted because they show structural and functional abnormalities in MRI studies. Calcium activity will be visualized in the OFC or VMS with either D1 or D2 specificity. We will compare neuronal activity in mice engaged in abnormal repetitive behaviors to examine the relationship between D1+ and D2+ striatal activity patterns and perseverative behaviors. Longitudinal data sets can then be analyzed for changes in network activity and links with behavior over hours, weeks, or months. OFC and VMS D1/D2 cellular activity associated with behavior will be studied using three different approaches (pharmacological, transgenic, and optogenetic) and time scales. 1) Mice will receive injections of pharmacological agents to induce transient perseverative behavior. 2) SAPAP3 knockout mice (a transgenic OCD model) will be studied longitudinally as perseverative behaviors develop over months. 3) OFC-VMS projections will be optogenetcially stimulated to induce perseverative behavior over weeks with calcium imaging before, during, and after stimulation.