Lowrie M B, Shahani U, Vrbová G
Department of Anatomy, University College London, U.K.
J Neurol Sci. 1990 Nov;99(2-3):249-58. doi: 10.1016/0022-510x(90)90159-k.
After injury to the peripheral nerve in rat pups at 5 days of age the development of the fast muscles tibialis anterior and extensor digitorum longus is impaired. Whether the length of time during which the muscles are denervated affects the degree of impairment was studied here. In one group of animals the peroneal nerve was crushed near to the muscles in one leg and further away from the muscles in the other leg. In another group of animals the sciatic nerve was crushed in one leg at 5 days and in some of these animals the nerve was crushed again 5-7 days later. The recovery of TA and EDL was measured by recording the weight and tension developed once reinnervation was complete. When the nerve was crushed close to the muscles, the muscles recovered significantly better than when the site of injury was further away, while delaying reinnervation by crushing the sciatic nerve a second time, impaired recovery of the muscles. It is concluded that the permanent impairment of fast muscles seen after neonatal nerve injury depends upon the length of time that the muscles are separated from their motoneurones.
在5日龄大鼠幼崽的外周神经损伤后，胫骨前肌和趾长伸肌等快肌的发育受到损害。本研究探讨了肌肉失神经支配的时间长度是否会影响损伤程度。在一组动物中，一侧腿部的腓总神经在靠近肌肉处被挤压，另一侧腿部的腓总神经在远离肌肉处被挤压。在另一组动物中，坐骨神经在5日龄时在一侧腿部被挤压，其中一些动物在5 - 7天后再次挤压神经。通过记录重新支配完成后肌肉的重量和产生的张力来测量TA和EDL的恢复情况。当神经在靠近肌肉处被挤压时，肌肉的恢复明显优于损伤部位较远时，而通过再次挤压坐骨神经延迟重新支配会损害肌肉的恢复。结论是，新生儿神经损伤后所见的快肌永久性损伤取决于肌肉与其运动神经元分离的时间长度。
