Generation of cell-specific tools to determine the role of spinophilin in regulating pathological responses to psychostimulant drugs of abuse

 描述：大脑由许多不同类型的神经元组成。例如，纹状体中的一类神经元被称为中棘神经元(MSN)。这些带刺的神经元之所以被称为突触，是因为它们包含树突，树突与来自皮质的含有谷氨酸的轴突和来自黑质的含有多巴胺的轴突形成连接，称为突触。MSN上的树突在称为突触后密度的电子致密区域中包含信号和支架分子。精神刺激药物滥用的作用是增加黑质多巴胺能神经元的多巴胺释放，这对定位于MSN树突棘的蛋白质有下游影响。一种名为嗜刺素的蛋白质在长期接触滥用的精神刺激性药物时会增加。纹状体MSN可分为直接通路神经元和间接通路神经元。目前，对不同类型MSN中突触蛋白功能的评价方法很少。这一点很重要，因为这两类MSN对精神刺激剂暴露的反应不同。我们建议的目的是确定这两类MSN中的亲脊髓蛋白在调节对可卡因和苯丙胺等慢性无毒和毒性精神运动兴奋剂方案的反应中的功能。确定亲脊髓蛋白在介导与这些药物滥用相关的病理过程中的细胞特异性作用，将确定新的靶向治疗成瘾和与长期滥用甲基苯丙胺相关的疾病，如帕金森病(PD)。在这一建议中，我们假设亲刺蛋白在两个MSN群体中在介导精神刺激剂诱导的病理过程中发挥着独特的作用。这一假设将使用以下具体目标进行检验：目标1。建立并验证在直接和间接途径MSN中表达他莫昔芬诱导的ICRE的小鼠系。我们将建立在直接或间接途径MSN中表达三苯氧胺可诱导的、改进的Cre(ICre)重组酶的小鼠系。目标2.(R21)。建立并验证FLOXED SPINOFIL(Spinofl/FL)小鼠。我们将产生一个新的转基因小鼠品系，它将与在Aim 1中产生的ICRE动物杂交，以创造MSN特异性的亲刺蛋白KO动物。目标3。(R33)。确定亲刺蛋白在精神刺激剂敏化的直接和间接途径MSN中的作用。我们将使用在AIMS 1和AIMS 2中创建的小鼠来确定这两个MSN群体中的亲刺蛋白在调节与精神刺激剂诱导的敏化相关的病理方面的功能。确定亲刺素在直接和间接途径MSN中对冰毒的作用。我们将使用AIMS 1和AIMS 2中创建的小鼠来确定这两个MSN群体中的亲刺蛋白在调节与甲基苯丙胺诱导的毒性相关的病理方面的功能。

 DESCRIPTION: The brain is made up of many different types of neurons. For example, one class of neuron in the striatum is called the medium spiny neuron (MSN). These spiny neurons are so called because they contain dendritic spines that form connections, called synapses, with glutamate-containing axons from the cortex and dopamine containing axons from the substantia nigra. The dendritic spines on the MSNs contain signaling and scaffolding molecules in an electron dense area called the postsynaptic density. Psychostimulant drugs of abuse act to increase dopamine release from nigral dopaminergic neurons, which has downstream effects on proteins that are localized to MSN dendritic spines. One protein, spinophilin, is increased upon chronic exposure to psychostimulant drugs of abuse. Striatal MSNs can be subdivided into two classes, direct and indirect pathway neurons. Currently there are very few ways to evaluate the function of synaptic proteins in the different classes of MSNs. This is important because the two classes of MSNs have different responses to psychostimulant exposure. The goal of our proposal is to determine the function of spinophilin in the two classes of MSNs in regulating responses to chronic non-toxic and toxic regimens of psychomotor stimulants such as cocaine and amphetamines. Determining the cell-specific role of spinophilin in mediating pathologies associated with these drugs of abuse will identify new pathways that can be targeted for treatment of addiction and disorders associated with long-term methamphetamine abuse, such as Parkinson disease (PD). In this proposal, we hypothesize that spinophilin plays a unique role in the two MSN populations in mediating psychostimulant-induced pathologies. This hypothesis will be tested using the following specific aims: Aim 1. (R21). Generate and validate mouse lines expressing tamoxifen-inducible, iCre in direct and indirect pathway MSNs. We will generate mouse lines that express a tamoxifen-inducible, improved Cre (iCre) recombinase in direct or indirect pathway MSNs. Aim 2. (R21). Generate and validate floxed spinophilin (Spinofl/fl) mice. We will generate a novel transgenic mouse line that will be crossed with the iCre animals generated in aim 1 to create MSN-specific spinophilin KO animals. Aim 3. (R33). Determine the role of spinophilin in direct and indirect pathway MSNs on psychostimulant sensitization. We will use mice created in aims 1 and 2 to determine the function of spinophilin in the two MSN populations on the regulation of pathologies associated with psychostimulant-induced sensitization Aim 4. (R33). Determine the role of spinophilin in direct and indirect pathway MSNs on METH toxicity. We will use mice created in aims 1 and 2 to determine the function of spinophilin in the two MSN populations on the regulation of pathologies associated with methamphetamine-induced toxicity.