不同时间修复周围神经损伤后神经生长因子含量的变化

目的观察在不同时期修复受损兔坐骨神经后,其局部神经生长因子(NGF)含量的变化及修复效果。方法新西兰大白兔24只,切断双侧坐骨神经,分为4组,每组6只。Ⅰ组为第5天进行神经修复组,Ⅱ组为第15天神经修复组,Ⅲ组为第25天神经修复组,Ⅳ组为即时神经修复组。修复后1周,各组随机抽取3只,取修复神经段的远端,进行神经生长因子(NGF)免疫组织化学检测,并进行灰度值分析;修复后2个月各组进行苏木素-伊红(HE)染色、透射电镜及轴突计数等检测。结果即时修复组与第5天神经修复组NGF含量分别高于其他2组(P<0.05),这2组间进行比较差异无统计学意义,第25天神经修复组含量最低,与其他组比较差异有统计学意义(P<0.05)。结论 5d内修复受损神经的局部NGF含量最高,其修复效果最佳。

Levels of nerve growth factor after peripheral nerve injury repair at different time spots

Objective To determine the level of local nerve growth factor （NGF） after repair of sciatic nerve injury in rabbits at different time spots and outcomes of the repair. Methods Twenty-four New Zealand white rabbits with artificially severed sciatic nerves of the both sides were randomized into 4 groups （n=6 each）, to receive nerve repair on day 5 （group I ）, 15 （group Ⅱ）, 25 （group Ⅲ） or immediately after injury （group IV）. At 1 week after repair, each 3 rabbits of the groups were randomly selected and harvested for the distal end of the repaired nerve which was then determine for NGF level by immunohistocbemistry and subjected to gray value analysis. At 2 months after repair, the four groups were studied with HE staining, transmission electron microscope （TEM） and axon counts. Results The levels of NGF in groups 1V and I were higher than those in the other groups （P〈0.05）, but were not significantly different between groups 1V and I. Group Ⅱ had the lowest level of NGF as compared with the other groups （P〈0.05）. Conclusion Nerve reDair within 5 days may yield highest level of local NGF and hence most favorable outcomes.