Estrogen Signaling in Nucleus Accumbens Astrocytes

项目摘要 星形胶质细胞已被证明在突触传递中起重要作用。虽然出现了 关于神经递质对星形胶质细胞的影响的研究，很少有人知道其他信号是如何传递的。 激素等分子影响星形胶质细胞信号传导。一种重要的激素， 神经元信号传导是雌二醇（E2）。这在诸如吸毒等动机行为中具有重要的相关性 成瘾，星形胶质细胞信号和雌激素信号影响药物寻求行为。但据 雌激素具体如何影响星形胶质细胞信号传导尚不清楚。这项提案将决定雌激素 影响星形胶质细胞信号传导及其随后的三方突触传递调节。对于这一提议，我 将集中在星形胶质细胞在核脑桥（NAc），因为这个大脑区域是至关重要的药物寻找 行为和显示结构和功能的性别差异。我假设E2会增加细胞内 通过与星形胶质细胞上的雌激素受体结合来增加星形胶质细胞中的钙。这种受体结合将导致 神经胶质递质释放，这反过来又会增加兴奋性突触传递。对于这个测试假设，我会 使用双光子显微镜检查星形胶质细胞中的钙活性。我首先要确定E2增加 NAc星形胶质细胞中的钙活性（Aim 1a）。然后我将确定位置和ER亚型以及细胞 表达ER的类型（目的1b）。对于目标2，我将测试E2对兴奋性突触的影响。 传输首先，我将通过测量缓慢的向内， 电流，星形胶质细胞谷氨酸释放的生物学测定（Aim 2a）。另外，我会监控兴奋性岗位 突触电流（EPSC）和确定负责EPSC变化的神经胶质递质（目的2b）。这 这项提案将填补雌激素如何影响星形胶质细胞信号传导的知识空白，这可能导致进一步的研究。 了解NAc相关行为的性别差异。这个建议也会让我掌握许多 研究技术，如双光子钙成像以及电生理学，这将促进我的 职业目标是成为一名独立的学术神经科学研究人员。

PROJECT SUMMARY Astrocytes have been shown to play an important role in synaptic transmission. While there is emerging research about the effects of neurotransmitters on astrocytes, there is little known about how other signaling molecules such as hormones impact astrocyte signaling. One important hormone that is well studied with neuronal signaling is estradiol (E2). This has important relevance in motivated behaviors such as drug addiction where astrocyte signaling and estrogen signaling affect drug seeking behavior. However, it is unknown how estrogen specifically affects astrocyte signaling. This proposal will determine how estrogen affects astrocyte signaling and its subsequent regulation of tripartite synaptic transmission. For this proposal, I will focus on astrocytes in the nucleus accumbens (NAc) as this brain region is critical for drug seeking behaviors and displays structural and functional sex differences. I hypothesize that E2 will increase intracellular calcium in astrocytes by binding to estrogen receptors on astrocytes. This receptor binding will lead to gliotransmitter release which will in turn increase excitatory synaptic transmission. To this test hypothesis, I will use two photon microscopy to examine calcium activity in astrocytes. I will first establish that E2 increases calcium activity in NAc astrocytes (Aim 1a). I will then determine the location and ER subtype as well as cell type in which ER is expressed (Aim 1b). For Aim 2, I will test the effects of E2 on excitatory synaptic transmission. First, I will determine where E2 stimulates gliotransmitter release by measuring slow inward currents, a biological assay of astrocytic glutamate release (Aim 2a). In addition, I will monitor excitatory post synaptic currents (EPSCs) and determine the gliotransmitter responsible for changes in EPSCs (Aim 2b). This proposal will fill the knowledge gap of how estrogen affects astrocyte signaling which could lead to further understanding of sex differences in NAc related behaviors. This proposal will also allow me to master many research techniques such as two photon calcium imaging as well as electrophysiology, which will promote my career goals to become an independent academic neuroscience researcher.