Neural Pathways Associated with Sympathetic Neuronal Recruitment in Humans

与人类交感神经元募集相关的神经通路

• 批准号: 217916-2013
• 负责人: Shoemaker, Kevin
• 金额: $ 4.15万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=523842
• 关键词: Neural; Pathways; Associated; Sympathetic; Neuronal

Understanding sympathetic discharge patterns, their modulation¸ and their cardiovascular impact, forms a major program of research in our laboratory. Through the sympathetic nervous system the brain emits bursts of neural activity that vary in frequency and the number of neurons making up the bursts. Our recent research exposed the various action potentials making up each burst and the existence of subpopulations that vary in conduction speed and recruitment patterns. Specifically, there exists a group of large and fast-conducting axons that are reserved for high-stress scenarios. What brain structures, and mechanisms regulate recruitment of these AP groups? A potent determinant of sympathetic outflow lies in the baroreceptors that sense blood pressure. The aims of the present research are to determine: 1) how sensory nerves from baroreceptors in the carotid sinus (neck) affect AP recruitment, 2) what brain structures are involved in the baroreflex control of AP recruitment, 3) the role of the paraspinal ganglia in this recruitment process, and 4) how a relatively common genetic variation (approximately 7% of Caucasians) in adenylate cyclase affects AP recruitment through augmented cardiac function and baroreceptor activation. The current research will combine existing microneurographic analysis of AP recruitment and functional neuroimaging of brain activation patterns, during manipulations of baroreceptor inputs and pharmacological manipulations of neurotransmission through the sympathetic synaptic pathways, to study the neurophysiologic basis of AP recruitment. This work will produce new knowledge regarding baroreflex-mediated AP recruitment and the impact of relevant modifiers of sympathetic outflow. In addition, the research will develop new technologies that enable baroreflex stimuli to be studied experimentally in the magnetic resonance imaging environment. Finally, the research will contribute to the long-standing need for information regarding the brain's involvement in blood pressure control with new techniques and technology to expose such mechanisms.

了解交感神经放电模式、其调节及其对心血管的影响，构成了我们实验室的一项主要研究计划。 通过交感神经系统，大脑发出神经活动的爆发，其频率和构成爆发的神经元数量各不相同。我们最近的研究揭示了构成每次爆发的各种动作电位以及传导速度和招募模式不同的亚群的存在。具体来说，存在一组大型且快速传导的轴突，是为高压力情况而保留的。哪些大脑结构和机制调节这些 AP 群体的招募？交感神经流出的一个有效决定因素在于感知血压的压力感受器。本研究的目的是确定：1​​) 颈动脉窦（颈部）压力感受器的感觉神经如何影响 AP 募集，2) 哪些大脑结构参与 AP 募集的压力反射控制，3) 椎旁神经节在此募集过程中的作用，以及 4) 腺苷酸环化酶中相对常见的遗传变异（大约 7% 的白种人）如何通过影响 AP 募集 增强心脏功能和压力感受器激活。目前的研究将结合现有的 AP 募集的显微神经图谱分析和大脑激活模式的功能性神经影像学，在压力感受器输入的操作和通过交感神经突触通路的神经传递的药理操作过程中，以研究 AP 募集的神经生理学基础。这项工作将产生关于压力感受反射介导的 AP 募集以及交感神经流出相关调节因子的影响的新知识。此外，该研究还将开发新技术，使压力反射刺激能够在磁共振成像环境中进行实验研究。 最后，这项研究将有助于通过新技术和新技术来揭示这种机制，从而满足对有关大脑参与血压控制的信息的长期需求。