壳聚糖导管结合碱性成纤维细胞生长因子修复大鼠坐骨神经缺损

Repair of rat sciatic nerve defect with chitosan duct combined with basic fibroblast growth factor

目的:应用含有碱性成纤维细胞生长因子的壳聚糖神经导管桥接大鼠坐骨神经缺损,观察其对神经再生的作用。方法:实验于2004-09/2005-05在辽宁医学院附属第一医院外科实验室完成。选择健康成年SD大鼠30只,按随机数字表法分为3组,复合导管组、自体神经移植组和单纯导管组,每组10只。分别采用壳聚糖加碱性成纤维细胞生长因子复合导管,自体神经移植和壳聚糖导管加生理盐水的单纯导管修复大鼠右后肢坐骨神经约10mm的缺损。术后4个月进行形态学(光镜、透射电镜、免疫组织化学、轴突图像分析)和神经电生理学(运动神经传导速度、复合肌肉动作电位)检测。结果:纳入大鼠30只,均进入结果分析。①术后4个月复合导管组各项指标与自体神经移植组相当,明显好于单纯导管组,400倍视野下,复合导管组再生神经的数目多于单纯导管组、直径(像素值)大于单纯导管组,差异有非常显著性意义[分别为(523.3±53.1),(452.2±32.1);45.63±4.61,36.36±3.51,F=15.56,37.76,P<0.01]。②透射电镜显示复合导管组再生神经纤维直径、轴突粗细、髓鞘厚度及形态学方面更接近自体神经移植组,而明显优于单纯导管组。③S-100蛋白免疫组织化学染色结果表明复合导管组有大量雪旺细胞增生,其数量和排列上达到自体神经移植水平。④电生理指标:复合导管组坐骨神经平均传导速度低于自体神经移植组,但高于单纯导管组,差异有显著性意义[分别为(17.53±2.76),(21.96±2.73),(14.37±2.43)m/s,F=5.528,P<0.05]。复合导管组复合肌肉动作电位接近于自体神经移植组,高于单纯导管组,差异有显著性意义[分别为(14.45±3.13),(15.62±3.40),(10.63±2.29)mV,F=9.905,P<0.01]。结论:壳聚糖加碱性成纤维细胞生长因子神经导管可以为神经修复提供一个良好的微环境,并显著促进神经的再生。

AIM： To observe effect of the nerve regeneration by combining chitosan nerve duct with basic flbroblast growth factor （bFGF） to bridge the rats＇ sciatic nerve defects. METHODS： This experiment was finished in the Surgical Laboratory of the First Affiliated Hospital of Liaoning Medical College from September 2004 to May 2005. Thirty healthy SD male rats were divided into three groups randomly, namely chitosan with bFGF （group A）, autograft （group B） and chitosan with natural serine （group C）, with 10 rats in each group. A 10-mm defect in sciatic nerve in the right hindlimb of each rat. Nerve defects were bridged by the 3 methods respectively. Four months after operation, the regenerating nerve was checked by morphology [light microscope, transmission electron microscope （TEM）, immunohistochemistry, axon image-analysis] and electrophysiology （mean conduct velocity and action potential of sciatic nerve）. RESULTS： All the 30 rats ware involved in the result analysis. （1）Four months after operation, each index of the group A was obviously better than that in the group C, and there were no differences between group A and group B. Under x400 microscope, the number of regenerating nerve fibers in group A was more than that of group C, and the diameter in group A was also bigger. There ware significant difference statistically [（523.3±53.1）, （452.2±32.1）; 45.63±4.61, 36.36±3.51, F=15.56, 37.76, P 〈 0.01]. （2）Under the TEM, the diameter of regenerating nerve, thickness of myelin sheath, size of axon and morphology in group A reached the level of group B, and obviously superior to those of group C. （3） S-100 protein immunohistochemistry showed there were much more regenerating Schwann cells in group A, and the number and alignment reached the standard of group B. （4）As for the results of electrophysiology, the mean conduct velocity of sciatic nerve in the group A was faster than that of the group C, but lower than that of the group B. There ware significant difference statistically [（17.53±2.76）, （21.96±2.73）, （14.37±2.43） m/s, F=5.528, P 〈 0.05]. The action potential of group A was nearly equal to that of group B and significantly higher than that of group C [（14.45±3.13）, （15.62±3.40）, （10.63±2.29） mV, F=9.905, P〈 0.01]. CONCLUSION： The chitosan nerve duct with bFGF can offer a suitable microenvironment for repairing the peripheral nerve defect and promote the nerve regeneration obviously.