2-Arachidonoylglycerol Signaling Relieves Stress-induced Anxiety

 描述(申请人提供)：虽然压力是情绪和焦虑症的主要风险因素，但压力转化为精神病理学的神经生物学机制尚不清楚。目前增强单胺能传递的治疗方法可以缓解症状，但可能无法纠正潜在的功能障碍，因为它们的长期成功率仅为40-60%。减少应激的病理效应的新的治疗方法可能会有广泛的临床应用。焦虑症与杏仁核过度活动有关。在啮齿动物中，应激增加了对杏仁基底外侧核(BLA)的兴奋性驱动。通过干预来缓和对BLA的兴奋性驱动力，BLA是恐惧和焦虑的关键调节器，这可能会减少压力诱导的精神病理。大麻素受体(CBR)在BLA内的谷氨酸能终末表达，CBR的激活降低了突触前释放的可能性。因此，内源性大麻素(ECB)系统完全可以缓冲应激诱导的对BLA的兴奋性驱动，从而减少应激诱导的病理。血乳酸中ECB的信号增强，ANANDAME(AEA)，可减少应激诱导的焦虑样行为。然而，2-花生四烯基甘油(2-AG)是大脑中含量最丰富的ECB，其在调节压力、焦虑和情绪方面的作用尚不清楚。JZL-184是一种主要的2-AG降解酶-单酰甘油脂肪酶的特异性抑制剂，最近的开发促进了这方面的进展，但仍有几个关键问题没有得到回答。2-AG信号通路能否缓冲应激诱导的行为失调？受损的2-AG信号是否会加剧应激诱导的行为失调？2-AG信号通过什么突触机制影响应激反应？我们开发了新的工具来从多个角度解决这些问题。我们已经从功能上验证了慢病毒载体能够过表达2-AG合成酶二酰甘油脂肪酶a(DAGLa)。我们还产生了DAGLa基因敲除(KO)和DAGLa条件性KO(DAGLaf/f)小鼠。这些新的工具使我们能够第一次测试2-AG信号与压力诱导的焦虑和抑郁行为之间的因果关系。这些研究的完成可以验证增强2-AG信号是治疗情绪和焦虑症的可行方法。这项建议还构成了一项严格的技术和专业培训计划。我将接受立体定向手术、质谱学、全细胞电生理学和病毒载体生成方面的培训。我将每月在实验室会议上陈述，每两年在Synaptic Journal Club上陈述，每年在部门研讨会和务虚会上陈述。我将通过每年在两次会议上展示我的作品来获得写作、演示和网络经验。我会每年至少准备一份手稿，编辑我同事的工作，并在Patel博士的监督下练习审稿和赠款。每年完成一项个人发展计划将有助于我与科尔布兰博士和帕特尔博士正式讨论我的进展和目标。这种培训构成了追求博士后机会和独立研究生涯的坚实基础。

 DESCRIPTION (provided by applicant): While stress is a major risk factor for mood and anxiety disorders, the neurobiological mechanisms by which stress is translated into psychopathology are poorly understood. Current therapeutics that augment monoaminergic transmission ease symptoms but likely do not correct underlying dysfunction as they exhibit long-term success rates of only 40-60%. Novel therapeutic approaches to reduce pathological effects of stress could have broad clinical applications. Anxiety disorders are associated with amygdala hyperactivity. In rodents, stress increases excitatory drive to the basolateral amygdala (BLA). Interventions which temper excitatory drive to the BLA, a key modulator of fear and anxiety, may reduce stress-induced psychopathology. Cannabinoid receptors (CBR) are expressed on glutamatergic terminals within the BLA and activation of CBRs reduces presynaptic release probability. Thus, the endogenous cannabinoid (eCB) system is perfectly poised to buffer stress-induced excitatory drive to the BLA and thereby reduce stress-induced pathology. Enhanced signaling of the eCB, anandamide (AEA), in the BLA reduces stress-induced anxiety-like behavior. However, the role of 2-arachidonoylglycerol (2-AG), the most abundant eCB in the brain, in regulating stress, anxiety, and mood is poorly understood. The relatively recent development of JZL-184, a specific inhibitor of the primary 2-AG degrading enzyme, monoacylglycerol lipase, has spurred progress on this front, but several critical questions remain unanswered. Can 2-AG signaling buffer stress-induced behavioral dysregulation? Does impaired 2-AG signaling exacerbate stress-induced behavioral dysregulation? By what synaptic mechanisms does 2-AG signaling influence stress responses? We have developed novel tools to address these questions from multiple angles. We have functionally validated a lentiviral vector to overexpress the 2- AG synthetic enzyme diacylglycerol lipase a (DAGLa). We have also generated DAGLa knockout (KO) and DAGLa conditional KO (DAGLaf/f) mice. These novel tools permit us to test, for the first time, a causal relationship between 2-AG signaling and stress-induced anxiety- and depressive-like behaviors. Completion of these studies could validate enhancing 2-AG signaling as a viable therapeutic approach for mood and anxiety disorders. This proposal also constitutes a rigorous technical and professional training plan. I will be trained in stereotaxic surgery, mass spectrometry, whole-cell electrophysiology, and viral vector generation. I will present monthly in lab meetings, biannually in Synaptic Journal Club, and yearly in a departmental seminar and retreat. I will gain writing, presentation, and networking experience by presenting my work at 2 conferences per year. I will prepare at least 1 manuscript per year, edit the work of my colleagues, and practice reviewing manuscripts and grants under the supervision of Dr. Patel. Yearly completion of an individual development plan will facilitate formal discussion of my progress and goals with Drs. Colbran and Patel. This training constitutes a solid foundation from which to pursue postdoctoral opportunities and an independent research career.