Profiling direct/indirect basal ganglia cells in restricted repetitive behavior

描述(由申请人提供)：限制性重复行为见于许多不同的神经发育、神经和精神障碍(例如自闭症、脆性X综合征、雷特综合征、痴呆症、强迫症和精神分裂症)。这些行为被归类为高度重复、不变和没有明显功能的行为。具体地说，在神经发育障碍中，表现出各种各样的重复行为，从有节奏的拍手或拍头到受限的兴趣和坚持相同的行为。虽然这些行为在这些患者群体中非常常见，但行为障碍的神经生物学基础相对未知，治疗具有挑战性。我们实验室的首要目标是阐明限制重复行为表达的神经生物学机制，并减少神经发育障碍患者的这些行为。限制性重复行为的动物模型使研究人员能够确定这些特殊的适应不良行为的神经生物学基础，而不会受到与神经发育障碍相关的其他生物学问题的影响或并发症。动物模型还允许在这些非常脆弱的人群尝试临床实验之前确定潜在药物治疗的临床疗效。来自受限重复行为的小鼠模型的证据表明，大脑中组成皮质-基底节回路的特定路径是不受调节的。这两种途径，直接途径和间接途径，通常以一种协调的、但相互拮抗的方式工作，以控制皮质激活和行为输出。我们实验室的数据表明，在表现出重复行为的小鼠中，间接途径的激活减少，这就留下了直接途径，使大脑皮层过度兴奋，产生异常行为。为了实现阐明重复行为的神经生物学基础的目标，我们将使用表现出自发重复行为的小鼠，并描述直接和间接基底节通路中的基因和蛋白质表达。首先，我们将使用荧光辅助细胞分选来分离直接途径细胞和间接途径细胞。然后，我们将使用RT-PCR阵列同时检测41个G蛋白偶联受体和44个信号转导分子在不同细胞组中的表达。然后，我们将分析这些插入细胞膜的受体的数量(因此具有生物学活性)，以及包装在细胞内小泡中的这些受体的数量。来自表现出高重复行为的小鼠(C58/J小鼠)的测量结果将与来自表现出不重复行为的密切相关的小鼠品系(C57BL/6J小鼠)的测量结果进行比较。根据我们的基因和蛋白质分析结果，我们将设计药物挑战实验，以确定前两个实验所阐明的任何靶点是否为受限重复行为提供了潜在的药物治疗。 公共卫生相关性：许多有发育障碍、神经问题或精神问题的人表现出受限的重复行为。这些行为本质上是重复的，没有明显的作用(例如，拍手、敲头、坚持相同和强迫)。我们正在研究哪些基因和蛋白质在表现出这些行为的小鼠和没有表现出这些行为的小鼠中表达不同，以了解大脑是如何控制这些行为的，以及哪些药物可以用来减少它们。

DESCRIPTION (provided by applicant): Restricted repetitive behaviors are seen in many different neurodevelopmental, neurological, and psychiatric disorders (e.g. autism, Fragile X syndrome, Rett syndrome, dementias, OCD, and schizophrenia). These behaviors are classified as highly repetitive, invariant, and without obvious function. In neurodevelopmental disorders specifically, there is a wide array of repetitive behaviors exhibited, ranging from rhythmic hand flapping or head banging to circumscribed interests and insistence of sameness. Although these behaviors are extremely common in these patient populations, the neurobiological basis of the behavior disorder is relatively unknown and treatment is challenging. The overarching goals of our lab are to elucidate the neurobiological mechanisms responsible for the expression of restricted repetitive behaviors and to reduce these behaviors in individuals with neurodevelopmental disorders. Animal models of restricted repetitive behaviors allow researchers to identify the neurobiological basis of these particular maladaptive behaviors without the influence or complication of other biological problems associated with the neurodevelopmental disorders. Animal models also allow for the determination of clinical efficacy of potential pharmacological therapies before clinical experimentation is attempted in these very vulnerable populations. Evidence from a mouse model of restricted repetitive behavior indicates that specific pathways in the brain that make up cortico-basal ganglia circuitry are disregulated. These two pathways, the direct and indirect pathways, normally work in a coordinated, yet antagonistic fashion to control cortical activation and behavioral output. Data from our lab suggests that the activation of the indirect pathway is reduced in mice that exhibit repetitive behavior and this leaves the direct pathway to overexcite the cortex and produce aberrant behaviors. To achieve our goals of elucidating the neurobiological basis of repetitive behavior, we will use mice that exhibit spontaneous repetitive behaviors and profile the gene and protein expression within the direct and indirect basal ganglia pathways. First, we will use fluorescence assisted cell sorting to separate direct from indirect pathway cells. Then we will use RT-PCR arrays to simultaneously measure the expression of 41 G-protein coupled receptors and 44 signal transduction molecules in the separate cell groups. We will then analyze the amount of those receptors that are inserted in to the cell membrane (and are therefore biologically active) and the amount of those receptors that are packaged in to intracellular vesicles. Measures from mice that exhibit high rates of repetitive behavior (C58/J mice) will be compared to measures from a closely related mouse strain (C57BL/6J mice) that express no repetitive behavior. Based on the results of our gene and protein analyses we will design drug challenge experiments to identify whether any of the targets elucidated by the first two experiments offer potential pharmacotherapy for restricted repetitive behaviors. PUBLIC HEALTH RELEVANCE: Many people with developmental disabilities, neurological problems, or psychiatric issues show restricted repetitive behaviors. These behaviors are repetitive in nature and serve no obvious function (e.g. hand flapping, head banging, insistence on sameness, and compulsions). We are investigating what genes and proteins are expressed differently in mice that show these kinds of behaviors and in mice that do not in order to learn how the brain controls these behaviors and what kind of drugs may be used to reduce them.