肌皮神经回植脊髓后神经再生与肱二头肌功能恢复的实验研究

Regeneration of musculocutaneous nerve and functional restoration of the biceps muscle after reimplantation of nerve to spinal cord

目的 研究大鼠臂丛神经根回植至脊髓后 ,神经纤维能否再生并有效恢复对靶器官的支配。 方法 健康SD大鼠 2 4只 ,制作臂丛根性撕脱伤后神经根回植术动物模型 ,分别于术后 3,6个月行神经元的逆行标记、神经电生理学、功能学测定、肌肉称重和神经肌肉HE染色等检测 ,评价回植术后肌皮神经再生和肱二头肌肌肉功能的恢复情况。 结果 术后 3,6个月 ,在相应的C6 脊髓前角均出现逆行标记的神经元 ,肱二头肌的肌肉动作电位恢复率 3个月时为 (30 .15±7.5 2 ) % ,明显低于 6个月的 (5 6 .0 1± 11.6 2 ) % (P <0 .0 1) ;肌肉收缩力恢复率 3个月时为 (2 3.14±5 .72 ) % ,明显低于 6个月的 (46 .91± 8.35 ) % (P <0 .0 1) ;肌肉湿重恢复率 3个月时为 (5 9.31±3.4 3) % ,明显低于 6个月的 (77.5 9± 5 .79) % (P <0 .0 1)。但将术后 3和 6个月时的再生神经的组织学变化进行比较时发现 ,差异并无显著性意义。 结论 臂丛神经根性撕脱伤后行神经根回植术 ,神经纤维可以再生 ,并在一定程度上恢复靶器官的功能。

Objective To evaluate nerve regeneration and reinnervation of target organ functionally and morphologically after reimplantation of nerve root to the spinal cord. Methods The animal models of reimplantation of musculocutaneous nerve to the spinal cord were made in 24 SD rats. After 3 months and 6 months, the musculocutaneous nerve regeneration and the funtional restoration of brachial biceps were evaluated by retrograde labellinig study with True Blue tracing, electrophysiologial examination, functional assessment, muscle wet weight and histological examination. Results At the 3rd and 6th months, the neurons labelled by True Blue were found in the ventral horn of the spinal cord. MAP's recovery rate of brachial biceps was (30.15±7.52)% in the 3rd month, which was significantly lower than (56.01±11.62)% in the 6th month ( P <0.01); Contractility's recovery rate of the muscle was (23.14±5.72)% in the 3rd month, which was significantly lower than (46.91±8.35)% in the 6th month ( P <0.01). Wet weight's recovery rate of the muscle was (59.31±3.43)% in the 3rd month, which was significantly lower than (77.59±5.79)% in the 6th month( P <0.01) too. However, there was no difference histologically in regenerative axons. Conclusions After reimplantation of nerve roots to the spinal cord, the axons can regenerate from neurons to reinnervate the muscle.