Identifying cellular mechanisms underlying abnormal repetitive behaviors using in vivo microscopy

 描述(由申请人提供)：强迫症(OCD)的特征是侵扰性的思想和强迫行为，以减少由这些强迫症产生的焦虑。在神经精神病学研究中，了解这种疾病的病理和分子特征仍然是一个相当大的挑战。这项研究的目的是调查神经回路中大规模神经活动模式的变化如何导致、期间和解决异常强迫行为。由来已久的理论表明，异常重复行为是由于纹状体直接和间接通路的失衡以及眼眶额叶皮质(OFC)活动的增加造成的。然而，直到最近才有可能检验这一理论。新推出的头戴式活体显微镜使我们能够同时观察清醒行为小鼠大脑深层结构中数百个神经元中的钙信号。将这种成像技术与特定于电路的操作工具相结合，我们可以开始测试OFC、直接和间接纹状体通路。为了检验神经活动如何随着持之以恒的行为而演变，我们将可视化OFC的活动及其在腹内侧纹状体(VMS)的靶点。这些区域之所以成为目标，是因为它们在核磁共振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的特异性。我们将比较参与异常重复行为的小鼠的神经元活动，以检查D1+和D2+纹状体活动模式与持久力行为的关系。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、数周或数月的行为之间的联系。将使用三种不同的方法(药理学、转基因和光遗传学)和时间尺度来研究与行为相关的OFC和VMS D1/D2细胞活动。1)小鼠将接受药物注射以诱导短暂的持久性行为。2)SAPAP3基因敲除小鼠(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投射将在刺激前、刺激中和刺激后进行数周的钙成像，以光遗传刺激诱导持久化行为。

 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.