夹伤与冰冻损伤大鼠股神经的选择性再生

背景：促进周围神经损伤后神经功能的恢复，一方面要尽量加快损伤处神经轴突的再生，另一方面需要提高近端与远端神经对接的精确度。目的：观察机械挤压伤与冰冻损伤2种损伤模式下周围神经损伤后神经轴突的选择性再生情况。方法：取健康8周龄雄性Sprauge-Dawley大鼠110只，分为3组，对大鼠行股神经主干夹伤、冰冻损伤或空白对照处理。造模后分别于第2，3，6，12周进行大体行为学检查，另外分别用纯蓝和荧光红标记错向长入的隐神经和正确长入的股神经肌支，逆行示踪标记运动神经元观测脊髓前角中示踪剂的分布及数目；造模后8周行电生理检查，并进行统计学分析。结果与结论：夹伤组与冰冻损伤组大鼠术侧后腿活动范围均缩小，伸腿功能均受限，但随时间的延长，功能有所恢复。股四头肌处可记录到运动诱发电位，2组之间差异无显著性意义(P > 0.05)。冰冻损伤组与夹伤组在荧光显微镜下均观察到脊髓前角红染神经元逐渐增加，造模后不同时间点夹伤组红染神经元数目显著高于冰冻损伤组(P < 0.05), 蓝色与紫色神经元数量逐渐减少。结果提示，保持神经束膜的完整性，即使损伤范围较大也能得到轴突再生中准确对接以及损伤肢体功能的恢复。

Selective regeneration of rat femoral nerve after crush injury and freeze injury

BACKGROUND: In order to promote the recovery of nerve function after peripheral nerve injury, we should try to accelerate the regeneration of injured nerve axons on one hand, and try to improve the accuracy of proximal and distal nerve docking on the other hand.  OBJECTIVE: To explore the selective regeneration of nerve axons after peripheral nerve injury in models with crush injury and freeze injury. METHODS: Totally 110 healthy male Sprauge-Dawley rats, 8 weeks old, were selected and randomly divided into three groups. The rates received crush injury, freeze injury and normal controlled surgery on femoral nerve trunk. At 2, 3, 6 and 12 weeks after modeling, general behavioral examination was performed, and then pure blue and red fluorescence were used to label the wrong-way ingrowth saphenous nerve and correct ingrowth femoral nerve muscular branches respectively; retrograde labeling the motor neurons in order to observe the distribution and amount of tracer in spinal cord anterior horn; electrophysiological examination was performed at 8 weeks after modeling, and analyzed statistically.     RESULTS AND CONCLUSION: Rats from both crush injury group and freeze injury group displayed decreased motion radius of hind limbs after surgery, and the stretch function was limited; but with time prolonging, the functions were recovered. The motor evoked potentials could be observed at the quadriceps, and there was no significant difference between two groups (P > 0.05). The number of neurons stained red in the spinal cord anterior horn was increased gradually in both crush injury group and the freeze injury group under fluorescence microscope. The number of neurons stained red in the crush injury group was significantly higher than that in the freeze injury group (P < 0.05), and the number of blue-stained and purple-stained neurons was decreased gradually. The results suggest that keeping the perineurium intact can gain accurate docking in axon regeneration and the recovery of injured limb functions, even though the damaged range is large.