PLGA导管修复大鼠坐骨神经缺损的实验研究

PLGA tube repairs sciatic nerve defect in rats

目的观察多孔PLGApoly(lactide-co-glycolide)导管修复大鼠坐骨神经缺损的效果。方法健康成年SD大鼠12只,分为自体神经移植组和PLGA导管组。两组动物分别人工造成右侧10mm的坐骨神经缺损后,PLGA导管组采用聚乳酸(polylactic acid,PLA)和聚羟基乙酸(polyglycolic acid,PGA)按75∶25的比例制成多孔PLGA管修复坐骨神经缺损。自体神经移植组采用坐骨神经进行桥接。术后4、8、12周,分别行坐骨神经功能指数检测,术后12周行快蓝(FastBlue)逆行示踪观察背根神经节(dorsal root ganglion,DRG)和脊髓神经元数目及行胫前肌湿质量测量;半薄和超薄切片观察再生纤维数目、直径及髓鞘厚度。结果坐骨神经功能指数比较,术后4周无显著性差异(P>0.05),但8周和12周有显著性差异(P<0.05),自体神经组优于PLGA管组。PLGA组DRG及脊髓中快蓝标记的神经元数目及胫前肌湿质量均不及自体神经组,差异有统计学意义(P<0.05);单位面积再生有髓纤维数目、直径和髓鞘厚度在PLGA管组与自体神经组比较,差异有统计学意义(P<0.05)。结论单用PLGA导管对坐骨神经缺损有一定的修复效果,但不及自体神经。

Objective To study the effects of poly （lactideco-glycolide） （PLGA） tube on the repair of sciatic nerve defect in rats. Methods Totally 12 adult SD rats were inflicted with a 10 mm defect in their right sciatic nerve, and then randomly received PLGA tube bridging （PLGA tube group） or autogenous nerve grafting （autotransplantation group）. The PLGA tube was compounded of 75% polylactic acid and 25% polyglycolic acid. The sciatic nerve function index （SFI） was observed in 4, 8 and 12 weeks after transplantation. In 12 weeks after transplantation, Fast Blue retrograde tracing was performed to assess the neurons in spinal cord and dorsal root ganglia, semi-thin and uhrathin sections were made to observe the number, diameter and myelin thickness of the regenerated axons, and the wet weight of tibialis anterior muscle was measured. Results The number of Fast Blue-labeled cells in the spinal cord and the dorsal root ganglia and the wet weight of tibial muscle were significantly less in PLGA group than in autotransplatation group （ P 〈 0.05 ）. So the number, diameter and myelin thickness of the regenerated axons were （ P 〈 0.05 ）. Conclusion The PLGA tube bridging can repair nerve defect to some extent, but the effect is still inferior to that of autogenous nerve grafting.