SENSORY AND RESPIRATORY INTEGRATION IN C1-C2 SPINAL CORD

描述（改编自申请人的摘要）： 这个建议是为了获得关于内脏组织的知识， 上颈段脊髓的感觉处理。 最近 观察导致了这个区域可能整合了内脏的概念， 信息来调节伤害性反应。 初步证据 大鼠表明具有下行投射的上颈神经元 处理有害输入，对感觉产生抑制作用 在较低的部分传输。 此外，一组降 C1-C2节段神经元有呼吸相放电。 没有明确 已经发现这些神经元对正常呼吸有贡献。 一 以前没有考虑过的可能函数是， 内脏传入高位颈段呼吸神经元可能影响 向下流出以产生呼吸困难的感觉。 整体 有一种假说认为，具有下行投射的上颈神经元 由内脏脊髓输入和迷走神经输入兴奋，因此可以调节 脊髓下段的神经元活动。 设计了具体目标 回答以下问题：1）什么是解剖学 上颈椎固有嵴髓核的分布和神经化学成分 神经元？ 2)上颈椎的化学活化/灭活 神经元影响脊髓臂旁或脊髓丘脑束神经元， 胸椎和腰骶段 3)C1-C2是否下降 脊髓本体神经元，包括呼吸神经元，由内脏兴奋， 传入输入 4)电生理学、形态学和 单个C1-C2神经元的神经化学特征， 细胞内渗透？ 神经解剖学、免疫组织化学和 神经生理学技术将用于确定基本信息 关于上颈椎固有脊髓神经元，包括呼吸神经元， 神经元 从这些研究中获得的数据将有助于了解 中枢神经机制，可能涉及的条件， 自主神经反射异常、无症状心肌缺血和呼吸困难。

DESCRIPTION (Adapted from the applicant's abstract): The objective of this proposal is to gain knowledge about the organization of visceral sensory processing in the upper cervical spinal cord. Recent observations led to the concept that this region may integrate visceral information to modulate nociceptive responses. Preliminary evidence in rats suggests that upper cervical neurons with descending projections process noxious inputs to produce inhibitory effects on sensory transmission in lower segments. Additionally a group of descending neurons in C1-C2 segments have respiration-phased discharge. No clear contribution to normal breathing has been found for these neurons. A possible function that has not been considered previously is that visceral input to high cervical respiratory neurons may influence the descending outflow to produce the sensation of dyspnea. The overall hypothesis is that upper cervical neurons with descending projections are excited by visceral spinal input and vagal input, and thus could modulate neuronal activity in lower spinal segments. Specific aims are designed to answer the following questions: 1) What is the anatomical distribution and neurochemical content of upper cervical propriospinal neurons? 2) Does chemical activation/inactivation of upper cervical neurons affect spinoparabrachial or spinothalamic tract neurons in thoracic and lumbosacral segments? 3) Are C1-C2 descending propriospinal neurons, including respiratory neurons, excited by visceral afferent inputs? 4) What are the electrophysiologic, morphologic and neurochemical characteristics of single C1-C2 neurons examined after intracellular penetration? Neuroanatomical, immunohistochemical and neurophysiological techniques will be used to determine basic information about upper cervical propriospinal neurons, including respiratory neurons. Data derived from these studies will provide understanding of central neural mechanisms which may be involved in conditions such as autonomic dysreflexia, silent myocardial ischemia, and dyspnea.