MODULATION OF SENSORY TRANSMISSION

感官传输的调制

• 批准号: 3397654
• 负责人: ROBERT A DAVIDOFF
• 金额: $ 10.35万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-09-01 至 1988-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3397654
• 关键词: axon; catecholamines; chemoreceptors; cutaneous sensory nerve; electrical potential; electrophysiology; fresh water environment; microelectrodes; nerve endings; neural conduction; neural information processing; neural transmission; neuropharmacology; neurotransmitters; pain; potassium; sensory feedback; spinal cord; spinal nerves

Cutaneous primary afferent neurons are complicated cells with specialized sites which include receptors responsible for receiving stimuli and transducing them into electrical potentials, axons capable of conducting to the spinal cord impulses generated in the periphery, and central terminals capable of releasing transmitter onto secondary neurons. The functions of these neurons can be regulated at these sites by various chemical, ionic, or synaptic means. The overall objectives of the present investigations are to understand more fully the mechanisms responsible for regulating the activity of afferent neurons. These aims follow from results of my recent previous studies which have centered on the control mechanisms affecting afferent terminals; such studies are not only widened, but will now be extended to include the peripheral end of the same cells. The project will continue investigations of the amphibian sensory system in the spinal cord maintained in vitro and will utilize electrophysiological and pharmacological techniques to study different parts of the afferent neuron in isolated preparations. The proposed experiments seek to elucidate the roles various chemicals located in the skin and nerves play in the excitation of nociceptive cutaneous receptors and/or in their sensitization to noxious stimuli. Investigations of this problem will use a skin-nerve preparation to determine the changes in single cutaneous afferents produced by noxious stimuli and by "algesic" substances. Ion-sensitive microelectrodes inserted in the gray matter of the spinal cord will be used to determine what neuronal elements and/or transmitters are responsible for the rises in extracellular K+ concentration produced by afferent activity and presumably important in regulating the excitability of afferent terminals. Intracellular recording and voltage clamping of afferent cell bodies will be used to ascertain the mechanism of action of catecholamines on the membranes of afferent neurons. The production of pain is a major medical, and human, concern. Thus, the proposed investigations pertain not only to an important area of neurobiology, but are also relevant to understanding the mechanisms of a symptom central to many disease states.

皮肤初级传入神经元是具有专门功能的复杂细胞 包括负责接收刺激的受体的位点 将它们转换成电位，轴突能够传导 脊髓冲动产生于外周和中央末端 能够将递质释放到次级神经元上。 的功能 这些神经元可以在这些位点通过各种化学、离子、 或突触手段。 本次调查的总体目标 更全面地了解负责调节的机制 传入神经元的活动。 这些目标是根据我最近的结果得出的 之前的研究主要集中在影响的控制机制上 传入终端；此类研究不仅扩大了范围，而且现在将 延伸至包括相同细胞的外周端。 该项目将 继续研究两栖动物脊髓中的感觉系统 在体外维持并利用电生理学和 研究传入神经元不同部分的药理学技术 在隔离制剂中。 拟议的实验旨在阐明各种化学物质的作用 位于皮肤和神经中，刺激伤害感受 皮肤受体和/或它们对有害刺激的敏感性。 对这个问题的调查将使用皮肤神经制剂来 确定有害物质产生的单次皮肤传入的变化 刺激和“止痛”物质。 离子敏感微电极 插入脊髓灰质将用于确定 哪些神经元元件和/或递质导致了 传入活动产生的细胞外 K+ 浓度，大概 对调节传入神经末梢的兴奋性很重要。 传入细胞体的细胞内记录和电压钳位将 用于确定儿茶酚胺的作用机制 传入神经元的膜。 疼痛的产生是医学和人类关注的一个主要问题。 因此， 拟议的调查不仅涉及一个重要领域 神经生物学，但也与理解神经生物学的机制有关 许多疾病状态的核心症状。