ANALYSIS OF THE RECURRENT RENSHAW CIRCUIT

循环伦肖电路的分析

• 批准号: 3404860
• 负责人: THOMAS M HAMM
• 金额: $ 12.62万
• 依托单位: ST. JOSEPH'S HOSP/MED CTR (PHOENIX)
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-04-01 至 1989-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3404860
• 关键词: axon; electrical potential; electrophysiology; innervation; interneurons; motor neurons; muscle cells; neural information processing; single cell analysis; spinal nerves; synapses

This proposal is concerned with analysis of the recurrent Renshaw circuit with the goal of contributing to our understanding of the role of recurrent inhibition in controlling the discharge of spinal motoneurons. The analysis of this disynaptic circuit will be accomplished primarily by the use of a technique for stimulating single motor axons in conjunction with spike-triggered averaging in order to record the small postsynaptic potentials in spinal motoneurons which result from such stimulation. Using these methods a number of specific issues will be addressed. The characteristics of single-axon recurrent inhibitory postsynaptic potentials (RIPSPs) will be documented as well as the relation of these characteristics to interneuronal discharge. The distribution of RIPSPs within a homonymous motor nucleus will be determined with respect to the motor-unit type of the stimulated axon and the motor-unit type of the motoneuron receiving the recurrent inhibition. The distribution of RIPSPs will also be examined for evidence of a "partitiioning" of RIPSPs, i.e., that RIPSPs produced by asons innervating a particular region of muscle are largest in those motoneurons which innervate that same region of muscle. Such a partitioning, if found, will be analyzed for contributions of topographic specificity in comparison to species specificity. These studies are expected to contribute to our understanding of the organization and functional significance of recurrent inhibition to spinal motoneurons and, in addition, to provide an approach for analyzing neuronal circuits in the mammalian spinal cord which involve di- and polysynaptic connections. The ultimate health-related goal of this study is to contribute to an understanding of altered function of segmental motor control mechanisms, such as occurs in such states as spasticity, rigidity and remor.

该提案涉及循环伦肖电路的分析 目的是帮助我们理解经常性的作用 抑制控制脊髓运动神经元的放电。 这 该双突触电路的分析将主要通过 使用刺激单运动轴突的技术 尖峰触发平均以记录小突触后 由这种刺激引起的脊髓运动神经元的电位。 使用 这些方法将解决一些具体问题。 这 单轴突周期性抑制突触后电位的特征 （RIPSP）以及这些之间的关系将被记录在案 神经元间放电的特征。 RIPSP的分布 在同名运动核内将确定关于 受刺激轴突的运动单位类型和轴突的运动单位类型 运动神经元受到反复抑制。 RIPSP的分布 还将检查 RIPSP“分区”的证据，即 由支配肌肉特定区域的阿森子产生的 RIPSP 是 在支配同一肌肉区域的运动神经元中最大。 如果找到这样的划分，将分析其贡献 与物种特异性相比的地形特异性。 这些研究预计将有助于我们了解 脊髓反复抑制的组织和功能意义 运动神经元，此外还提供了一种分析神经元的方法 哺乳动物脊髓中涉及双突触和多突触的回路 连接。 这项研究与健康相关的最终目标是 有助于理解节段运动功能的改变 控制机制，例如发生在痉挛、僵硬等状态下 和悔恨。