FATIGUE OF SEGMENTAL MOTOR MECHANISMS

这个项目的目标是制定一个将研究联系起来的标准 减量动物(麻醉猫)运动单位疲劳性的研究 在有意识的人类身上做好准备。此外，目标是 是将发动机部件疲劳性的研究与 有序运动单位招募现象与亨纳曼的“规模” 该项目基于两个具体目标。第一， 考察了运动神经元的自适应特性的前提 在连续和短暂的重复电流注入期间 与他们的功能阈值和作用力有关- 它们提供的肌肉纤维的生产能力。这一目标将 在深度麻醉的猫身上进行测试，通过测量生物物理 脊髓运动神经元的特性及其力输出 电机部件和测试之间的关联 单神经元放电率的性质和变化 通过细胞内注入可变的去极化电流 强度、持续时间、波形和间歇性。第二 特定目标检验发动机单元疲劳的命题 在持续和各种形式的间歇激活过程中 与他们的正常招聘顺序和高峰期相关 部队生产能力。第二个目标将在#年进行测试 与第一个目标类似的动物制剂，通过测量一个 后肢肌肉的各种运动单位特性，包括 对新开发的疲劳诱导刺激的反应 养生法旨在以相对类似的方式强调运动单位 方式，无论它们的收缩时间，融合 频率和峰值部队生产能力。 预计这些研究将有助于提供关于 电机控制中尚未解决的基本问题 解决了。此外，这项工作对 骨科，运动医学，疲劳性，在 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，以及对于新兴领域 马达假肢。

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.