Dopamine function, inflammation and connectivity in PTSD

项目摘要 这项研究的目的是评估压力诱导的多巴胺功能的变化， 创伤后应激障碍炎症反应与连接性和行为症状 （PTSD）。我们小组和其他人对创伤后应激障碍的成像研究描述了激活和功能的改变， 各种大脑区域之间的连接，包括内侧前额叶皮层（mPFC），杏仁核， 海马体。尽管对PTSD中回路功能障碍的认识越来越多，但功能性神经影像学研究 迄今为止进行的研究还没有提供关于神经递质系统和神经生物学的足够信息。 影响这些回路以维持创伤后应激障碍症状的途径。创伤后应激障碍是一个重要的公共卫生问题， 影响到7%至8%的普通人口，性虐待受害者的发生率更高（10%）。 心理社会压力和创伤激活神经内分泌和免疫系统， 炎症标志物的浓度。激活免疫系统和释放炎性细胞因子 破坏中皮层/边缘多巴胺系统，并与焦虑，再体验， 这在创伤后应激障碍中很突出我们小组的研究结果表明， 多巴胺，如通过微透析测量的，在马槟榔碱诱导的炎症动物模型中。升高 炎症标志物（如血浆CRP和细胞因子）也与破坏的中脑边缘和 中皮层回路，包括腹侧纹状体和杏仁核与mPFC的功能连接减少， 与重度抑郁症患者的焦虑症状相关，特别是在共病患者中 创伤后应激障碍迄今为止，功能性脑成像研究已经概述了创伤后应激障碍的神经回路，但这些成像 测量仅提供大脑功能的一般测量（例如血流量），而不涉及特定的 神经化学途径拟议的研究将通过审查以下内容来解决这一知识差距 问题1）在PTSD患者中，压力诱导的前额叶和边缘DA神经传递是否减少？（二） 应激诱导的炎症生物标志物在PTSD中是否更高并与症状严重程度相关？（3）是 与PTSD和症状相关的功能行为和连接的静息测量中断 严重性？我们提出的工作建立在我们实验室在创伤后应激障碍成像方面的经验基础上，包括证明 mPFC功能的血流量和血氧水平依赖性降低。我们的长期目标是提高我们的 应激诱导的多巴胺能功能和PTSD炎症反应的机制框架，以及 确定可以预测PTSD症状及其严重程度的机制，以改善未来的治疗 接近。

PROJECT SUMMARY The objective of this research proposal is to assess changes in stress-induced dopamine function and inflammatory response with connectivity and behavioral symptoms in posttraumatic stress disorder (PTSD). Imaging studies of PTSD from our group and others have described altered activation and functional connectivity between a variety of brain regions including the medial prefrontal cortex (mPFC), amygdala, and hippocampus. Despite increasing knowledge of circuit dysfunction in PTSD, functional neuroimaging studies performed to date have not provided adequate information about neurotransmitter systems and neurobiological pathways that affect such circuits to maintain PTSD symptoms. PTSD is an important public health problem that affects 7 to 8 % of the general population with higher rates of occurrence in victims of sexual abuse (10%). Psychosocial stress and trauma activate neuroendocrine and immune systems and elevate circulating concentrations of inflammatory markers. Activation of the immune system and release of inflammatory cytokines disrupts the mesocortical/limbic dopamine system and are associated with symptoms of anxiety, re-experiencing, arousal and avoidance that are prominent in PTSD. Findings from our group demonstrate blunted release of dopamine, as measured by microdialysis, in a cytokine-induced inflammatory animal models. Elevated inflammatory markers (e.g. plasma CRP and cytokines) were also associated with disrupted mesolimbic and mesocortical circuits, including decreased ventral striatum and amygdala to mPFC functional connectivity, in association with symptoms of anxiety in major depressive disorder, and particularly in patients with comorbid PTSD. Functional brain imaging studies to date have outlined a neural circuitry of PTSD but these imaging measures provide only general measures of brain function (e.g. blood flow) and do not address specific neurochemical pathways. The proposed research will address this knowledge gap by examining the following questions 1) Is stress-induced prefrontal and limbic DA neurotransmission reduced in patients with PTSD?, 2) Are stress-induced inflammatory biomarkers higher in PTSD and associated with symptom severity? and 3) Are disruptions in resting measures of functional behavior and connectivity associated with PTSD and symptom severity? Our proposed work builds on our laboratory’s experience in imaging PTSD including demonstration of blood flow and blood oxygen level-dependent reductions in mPFC function. Our long-term goal is to improve our mechanistic framework of stress-induced dopaminergic function and the inflammatory response in PTSD, and to identify mechanisms that can predict PTSD symptoms and their severity that may improve future treatment approaches.