PHYSIOLOGY OF MUSCARINIC SYNAPSES IN SYMPATHETIC GANGLIA

交感神经节毒蕈碱突触的生理学

• 批准号: 3401843
• 负责人: JOHN P HORN
• 金额: $ 5.84万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-07-01 至 1987-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3401843
• 关键词: axon reaction; denervation; electrophysiology; fresh water environment; innervation; neuroanatomy; parasympathetic nervous system; slow potential; synapses

Sympathetic ganglia convey commands that implement reactions to bodily stress. The long-term goals of this project are to understand how three slow synaptic potentials contribute to the normal integrative function of bullfrog sympathetic ganglia and to identify factors that regulate the expression of muscarinic synapses in ganglia. The working hypotheses for this proposal are that 1) ganglia contain physiologically specialized and antomically separate functional channels that modulate different classes of peripheral end organs, 2) slow potentials enable ganglion cells to generate characteristic patterns of activity to drive optimally their specific targets and 3) the synaptic connections of ganglion cells regulate their expression of muscarinic synapses. Isolated preparations containing the ninth and tenth paravertebral ganglia will be used to study the muscarinic excitatory postsynaptic potential (epsp), the muscarinic inhibitory post synaptic potential (ipsp) and a peptidergic epsp mediated by leuteinizing hormone releasing hormone (LHRH). Three physiologically identifiable types of neurons (fast B, slow B, C) within these ganglia innvervate viscera in the lower abdomen (e.g. bladder) and other targets in the hindlimbs (e.g. exocrine glands, vasculature, sensory receptor). However, the relation between these cell types and the hypothesized functional channels is uncertain. A combination of electrophysiological and anatomical methods will be used to provide a detailed description of ganglionic synapses, the morphology of identified sympathetic neurons and the projections of identified cells into cutaneous, motor and visceral branches or peripheral nerves. Next, reports that muscarinic epsps are variable in their voltage-sensitivity will be pursued to determine how heterogeneity in muscarinic excitation is related to the subclasses of B cells and how muscarinic epsps differ in their effects upon repetitive firing. Then muscarinic inhibition of repetitive firing will be analyzed by voltage clamping C cells. After the full range of muscarinic modulation of repetitive firing has been characterized, the influence of specific connections between the ganglia, cord and periphery upon the differential expression of muscarinic responses in ganglion cell types will be studied during axotomy, denervation and re-innervation.

交感神经节传达命令，执行对身体的反应， 应力 本项目的长期目标是了解三个 慢突触电位有助于正常的整合功能， 牛蛙交感神经节，并确定调节因素， 神经节中毒蕈碱突触的表达。 工作假设 这个建议是：1）神经节含有生理上专门的， 自动分离的功能通道，调节不同类别的 外周终末器官，2）慢电位使神经节细胞产生 活动的特征模式，以最佳方式推动其特定的 3）神经节细胞的突触连接调节其 毒蕈碱突触的表达。 分离的制剂，含有 第九和第十椎旁神经节将用于研究毒蕈碱 兴奋性突触后电位（epsp），毒蕈碱抑制性突触后电位， 突触电位（ipsp）和亮氨酸化介导的肽能epsp 激素释放激素（LHRH）。 三种生理上可识别的类型 神经元（快B，慢B，C）在这些神经节内的内脏 下腹部（例如膀胱）和后肢中的其他目标（例如， 外分泌腺、血管系统、感觉受体）。 然而，关系 这些细胞类型和假设的功能通道之间的联系是 不确定 将采用电生理学和解剖学方法相结合的方法 为了提供神经节突触的详细描述， 识别的交感神经元和识别的细胞投射到 皮肤、运动和内脏分支或周围神经。 接下来，报告 毒蕈碱EPSP在其电压敏感性方面是可变， 为了确定毒蕈碱兴奋的异质性如何与 B细胞的亚类以及毒蕈碱epsps在它们的 重复射击的影响。 然后毒蕈碱抑制重复性 将通过电压箝位C单元来分析点火。 全系列之后 重复放电的毒蕈碱调制的特点， 神经节、脊髓和外周之间特定联系的影响 对神经节细胞中毒蕈碱反应的差异表达 将在轴突切断、去神经支配和神经再支配期间研究类型。