Côté C, Faulkner J A
Am J Physiol. 1986 Jun;250(6 Pt 1):C828-33. doi: 10.1152/ajpcell.1986.250.6.C828.
Extensor digitorum longus (EDL) muscles of rats were grafted with the nerves intact. Sixty days after grafting, single motor units were isolated and characterized in terms of fatigability and morphology. The distribution of fatigue indexes for motor units in control muscles revealed two main peaks, whereas in grafts no clear peaks were observed, fatigue indexes being distributed more evenly over the entire range. This difference in the distribution of fatigue indexes of motor units may explain the increased resistance to fatigue observed for whole grafts compared with whole EDL muscles. An inverse linear relationship was found between maximum tetanic tensions and the fatigue indexes of motor units from control and grafted EDL muscles. The distribution of fiber areas for single motor units was broader in grafts than in control EDL muscles, but the mean innervation ratio was not different. In approximately 20% of the units mapped in grafts, fibers were clustered tightly within a small portion of the total cross section, suggesting axonal sprouting during regeneration.
将大鼠的趾长伸肌（EDL）在神经完整的情况下进行移植。移植60天后，分离出单个运动单位，并根据疲劳性和形态进行表征。对照肌肉中运动单位的疲劳指数分布显示出两个主要峰值，而在移植肌肉中未观察到明显峰值，疲劳指数在整个范围内分布更为均匀。运动单位疲劳指数分布的这种差异可能解释了与整个EDL肌肉相比，整个移植肌肉观察到的抗疲劳能力增强的原因。在对照和移植的EDL肌肉中，发现最大强直张力与运动单位的疲劳指数之间存在反线性关系。移植肌肉中单个运动单位的纤维面积分布比对照EDL肌肉更宽，但平均支配率没有差异。在移植肌肉中绘制的约20%的单位中，纤维紧密聚集在总横截面积的一小部分内，表明再生过程中存在轴突发芽。
