MOTOR UNIT ORGANIZATION

电机组结构

• 批准号: 3413998
• 负责人: CARLTON C HUNT
• 金额: $ 16.24万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-09-01 至 1994-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3413998
• 关键词: axon; cats; denervation; fatigue; innervation; motor neurons; muscle tension; myofibrils; neural conduction; radiotracer; synapses; tetany

This research aims to study motor units having different axonal conduction velocities with respect to the number of muscle fibres innervated, their cross sectional areas and specific tensions (kg/cm2). The data should indicate which of these variables is responsible for the precise and important relation between axonal size and force developed in fatigue-resistant motor units. In such units log 10 maximal tetanic tension shows a nearly linear relation to axonal conduction velocity. Single motor axons to superficial lumbrical muscle of cat will be isolated in ventral root, conduction velocity determined and muscle fibres of a unit labeled with C14 2-deoxyglucose during activity. Using superficial lumbrical which has 2 heads, comparisons between pairs of units can be made in single animals, avoiding scatter in data introduced by interanimal variation. Numbers and diameters of labeled fibres will be measured; specific tension will be derived from maximal tetanic tension divided by cross sectional area of unit's fibres. Similar measurements will be made after disuse (tenotomy) to determine which variables are altered. This is relevant to clinical conditions in which disuse leads to profound changes in muscle. Studies will also be made in muscles reinnervated after nerve crush to determine fibre numbers, areas, specific tensions and spatial distributions. This has clear implications for clinical problems of nerve injury and reinnervation.

这项研究旨在研究具有不同轴突传导的电机单元 关于支配的肌肉纤维数量的速度 横截面区域和特定张力（kg/cm2）。数据应该 指出这些变量中的哪一个负责确切和 轴突尺寸和力之间的重要关系 抗疲劳的电机单元。在此类单元中，日志10最大的破蛋张力 显示与轴突传导速度几乎线性的关系。单电动机 CAT浅表肌肉的轴突将在腹侧分离 根，传导速度确定和标记为单位的肌肉纤维 在活性过程中与C14 2-脱氧葡萄糖。使用浅表卷曲 有2个头，可以在一对单位之间进行比较 动物，避免通过暂停变异引入的数据中散射。 将测量标记纤维的数量和直径；具体张力 将源自最大的四张力张力除以横截面 单元纤维区域。废弃后将进行类似的测量 （替术）确定哪些变量发生了变化。这与 废弃的临床条件会导致肌肉发生深刻变化。 在神经压碎后，还将在肌肉中进行研究 确定纤维数量，区域，特定紧张局势和空间 分布。这对神经的临床问题有明显的影响 伤害和加剧。