FATIGUE OF SEGMENTAL MOTOR MECHANISMS

分段电机机构的疲劳

• 批准号: 3410188
• 负责人: DOUGLAS A STUART
• 金额: $ 15.16万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-09-01 至 1992-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3410188
• 关键词: cats; degenerative motor system disease; fatigue; neuromuscular function; neuromuscular system

The goal of this project is to develop a rubric that links the study of motor-unit fatigability in reduced-animal (anesthetized-cat) preparations with that in conscious humans. In addition, the goal is to link the study of motor-unit fatigability to that of the orderly motor-unit recruitment phenomenon and Hennaman's "Size Principle." The project is based upon two specific aims. The first examines the premise that the adaptive properties of motoneurons during both sustanied and brief repetitive current injections are associated with their functional thresholds and the force- producing capacity of the muscle fibers they supply. This aim will be tested in deeply anesthetized cats by measuring the biophysical properties of spinal motoneurons and the force output of their motor units and testing for an association between these properties and changes in mononeuronal firing rates brought about by intracellular injection of depolarizing currents of variable strength, duration, waveform and intermittency. The second specific aim tests the proposition that the fatigue of motor units during sustained and various forms of intermittent activation are associated with their normal recruitment order and their peak force-producing capacity. This second aim will be tested in animal preparations similar to the first aim, by measuring a variety of motor-unit properties in a hindlimb muscle, including the responses to newly developed fatigue-inducing stimulus regimens designed to stress the motor units in a relatively similar manner, irrespective of their contraction times, fusion frequencies and peak force-producing capacities. It is anticipated that these studies will contribute information on fundamental issues in motor control that have not yet been resolved. Furthermore, the work has profound implications for orthopedics, sports medicine, the fatigability that is evident in many neuromuscular diseases, motor recovery after brain damage and peripheral neuromuscular damage, and for the emerging field of motor prosthetics.

这个项目的目标是开发一个标题， 运动单位疲劳性的减少动物（麻醉猫） 在有意识的人类中进行准备。 此外，目标 是将运动单元疲劳性的研究与 有序的机动部队招募现象和Hennaman的“规模 原则“该项目基于两个具体目标。 第一 研究的前提是运动神经元的适应性 在持续和短暂的重复电流注入期间， 与他们的功能阈值和力相关- 它们所提供的肌肉纤维的生产能力。 这一目标将 在深度麻醉的猫中进行测试，通过测量生物物理 脊髓运动神经元的特性及其力输出 运动单位和测试这些之间的关联 单神经元放电率的性质和变化 通过细胞内注射不同浓度的去极化电流 强度、持续时间、波形和不稳定性。 第二 特定目标测试运动单位疲劳的命题 在持续和各种形式的间歇激活期间， 与正常的招募顺序和 生产能力。 第二个目标将在 与第一个目的类似的动物制剂，通过测量 后肢肌肉中的各种运动单位特性，包括 对新产生的疲劳诱导刺激的反应 方案旨在强调运动单位在一个相对类似的 方式，不管他们的收缩时间，融合 频率和峰值力产生能力。 预计这些研究将提供以下信息： 运动控制中的基本问题， 解决了 此外，这项工作对以下方面具有深远的影响： 骨科，运动医学，疲劳，这是明显的， 许多神经肌肉疾病，脑损伤后的运动恢复 和周围神经肌肉损伤， of motor运动prosthetics假肢.