Functional consequences of cocaine self-administration on astrocytes

可卡因自我给药对星形胶质细胞的功能影响

基本信息

批准号：
10682221
负责人：
Kathryn Joanna Reissner
金额：
$ 34.3万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-05-01 至 2028-02-29
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10682221
关键词：
Abstinence Acute Adenosine Adenosine A1 Receptor Affect Animal Behavior Area Astrocytes Atrophic Automobile Driving Behavior Behavioral Biosensor Brain Calcium Signaling Cell model Cell physiology Cells Chronic Cocaine Communication Coupled Data Dopamine Dopamine D1 Receptor Dopamine D2 Receptor Drug Targeting Drug abuse Electrophysiology (science)Exhibits Functional disorder G-Protein-Coupled Receptors GTP-Binding Proteins Glutamates Goals Homeostasis Image Impairment In Situ Incubated Intervention Intravenous Knowledge Label Ligands Measures Mediating Neuroglia Neurons Neurophysiology - biologic function Nucleus Accumbens Pathologic Pathology Pharmaceutical Preparations Phenotype Physiological Physiology Public Health Pump Rat Transgene Rattus Regulation Role Saline Self Administration Signal Transduction Slice Structure Substance Use Disorder Surface Synapses Synaptic Transmission Testing Time antagonist cocaine craving cocaine exposure cocaine seeking cocaine self-administration cocaine use craving designer receptors exclusively activated by designer drugs drug seeking behavior experimental study fluorescence imaging high resolution imaging in vivo inhibitor male multimodality neural neural circuit neuroadaptation novel patch clamp pharmacologic presynaptic prolonged abstinence receptor response reward circuitry stimulant use disorder synaptic depression synaptic inhibition treatment strategy

项目摘要

Project Summary/Abstract Accumulating evidence has identified nucleus accumbens astrocytes as salient targets of drug abuse. For example, numerous studies indicate that rat self-administration of multiple drug classes results in impaired glutamate homeostasis, as well as decreased structural features and synaptic colocalization of nucleus accumbens astrocytes. Preliminary data for this proposal reveal that male rat accumbens astrocytes exhibit striking (~40%) reductions in surface area, volume, and synaptic colocalization 45 days after 10 days of long- access (6h/d) cocaine self-administration. These findings suggest loss of physiological function of astrocytes as regulators of neural circuits. However, the mechanism(s) driving these observations are unknown, as are the consequences to neural function. We hypothesize that astrocyte pathology underscores the neural adaptations and increased measures of craving observed across prolonged abstinence (also known as incubation). Accordingly, the goal of this proposal is to define the relationship between cocaine self- administration and the onset of astrocyte dysfunction in the nucleus accumbens, as well as the relationship between astrocyte dysfunction, synaptic transmission, and behavior. Aim 1 will assess the effects of operant cocaine self-administration on evoked Ca2+ responses in accumbens astrocytes as a function of both self- administration and abstinence, and will determine the functional significance of astrocyte Ca2+ to cocaine seeking behaviors. Aim 2 will examine how cocaine self-administration affects the ability of astrocytes to negatively regulate excitatory synaptic transmission in D1 and D2 receptor-positive medium spiny neurons. Lastly, Aim 3 will establish the role of dopamine and G protein-mediated astrocyte signaling in the pathological effects of cocaine on accumbens astrocyte structure. For each aim, we will evaluate endpoints as a function of time across abstinence. These objectives will collectively be accomplished by leveraging a multimodal approach that spans cellular physiology to circuit analysis and animal behavior, combining rat cocaine self- administration with high-resolution imaging of fluorescently-labeled astrocytes, acute slice imaging of Ca2+- labeled astrocytes using a photoconvertible Ca2+ indicator (astro-CaMPARI2), astrocyte DREADD stimulation, astrocyte Ca2+ depletion using an astrocyte-expressed PMCA2 Ca2+ pump, whole cell patch-clamp electrophysiology, neuronal subtype-specific analyses using Drd1a-Cre and Drd2-Cre transgenic rats, and fluorescent imaging of an adenosine biosensor GRABAdo. Collectively, these studies will define the relationship between astrocyte dysfunction across abstinence from cocaine self-administration with neural physiology and behavior.

项目概要/摘要越来越多的证据表明伏隔核星形胶质细胞是药物滥用的显着目标。为了例如，大量研究表明，大鼠自行服用多种药物会导致谷氨酸稳态，以及细胞核结构特征和突触共定位的减少伏隔星形胶质细胞。该提案的初步数据表明，雄性大鼠伏隔星形胶质细胞表现出经过 10 天的长期刺激后 45 天，表面积、体积和突触共定位显着减少 (~40%) 获取（6小时/天）可卡因自我给药。这些发现表明星形胶质细胞生理功能丧失作为神经回路的调节器。然而，驱动这些观察的机制尚不清楚，因为对神经功能的影响。我们假设星形胶质细胞病理学强调了神经在长期禁欲期间观察到的适应和渴望增加的措施（也称为孵化）。因此，本提案的目标是界定可卡因自体与可卡因之间的关系。给药与伏隔核星形胶质细胞功能障碍的发生及其关系星形胶质细胞功能障碍、突触传递和行为之间的关系。目标 1 将评估操作的影响可卡因自我给药对伏隔星形胶质细胞中诱发 Ca2+ 反应的影响作为自我给药的函数给药和戒断，并将确定星形胶质细胞 Ca2+ 对可卡因的功能意义寻求行为。目标 2 将检查可卡因自我给药如何影响星形胶质细胞的能力负调节 D1 和 D2 受体阳性中型多棘神经元的兴奋性突触传递。最后，目标 3 将确定多巴胺和 G 蛋白介导的星形胶质细胞信号传导在病理学中的作用。可卡因对伏隔星形胶质细胞结构的影响。对于每个目标，我们将根据以下函数评估终点禁欲的时间。这些目标将通过利用多式联运共同实现该方法涵盖细胞生理学、电路分析和动物行为，结合了大鼠可卡因自我荧光标记星形胶质细胞高分辨率成像、Ca2+- 急性切片成像使用光转换 Ca2+ 指示剂 (astro-CaMPARI2) 标记星形胶质细胞，星形胶质细胞 DREADD 刺激，使用星形胶质细胞表达的 PMCA2 Ca2+ 泵、全细胞膜片钳去除星形胶质细胞 Ca2+ 电生理学，使用 Drd1a-Cre 和 Drd2-Cre 转基因大鼠进行神经元亚型特异性分析，以及腺苷生物传感器 GRABAdo 的荧光成像。总的来说，这些研究将定义这种关系星形胶质细胞功能障碍与可卡因自我给药戒断与神经生理学之间的关系行为。