血管化纳米复合材料n-PDLLA/PRGD/HAP/VPA神经导管修复大鼠坐骨神经缺损

Vascularized Nano Composite Material PDLLA/PRGD/HAP/VPA Nerve Conduit Repairs Defects of Sciatic Nerve in Rats

目的:探讨血管化复合纳米材料n-PDLLA/PRGD/HAP/VPA神经导管对损伤大鼠坐骨神经再生及修复的效果。方法:将60只SPF级雄性成年SD大鼠随机平均分为4组,均于右侧制备坐骨神经15mm缺损模型。A组:PDLLA/PRGD/HAP/VPA神经导管桥接+局部注射血管内皮生长因子基因(pHVEGF16);B组:单纯PDLLA/PRGD/HAP/VPA神经导管桥接;C组:自体神经移植;D组:硅胶管桥接。术后每隔2周检测坐骨神经功能指数(SFI),每4周检测腓肠肌湿重,3个月后取材并进行神经肌肉电生理、组织学和透射电子显微镜观察等检测。结果:A组大鼠运动功能恢复最快(P<0.05),腓肠肌湿重检测优于B、D组(P<0.05)。术后12周,A组坐骨神经传导速度、轴突计数结果较B、D组好(P<0.05)。A组再生坐骨神经纤维较B、D组排列密集且成熟,接近正常神经组织,脱髓鞘改变和雪旺细胞空泡样改变少见。结论:运用n-HAP/PRGD/PDLLA/VPA复合神经材料导管合并局部注射pHVEGF16对大鼠15mm坐骨神经缺损显示出了良好的神经修复效果,说明此种复合神经材料导管对于损伤神经再生和血管化效果明显。

Objective:To investigate the effect of n-PDLLA/PRGD/HAP/VPA nerve conduit on the injury of sciatic nerve in rats.Methods:Sixty adult male SD rats were randomly divided into 4groups in average to prepare the right sciatic nerve 15 mm defect models.Rats in A group were connected with PDLLA/PRGD/HAP/VPA nerve conduit combining with local injection of vascular endothelial growth factor gene(pHVEGF16)while those in B group bridged with PDLLA/PRGD/HAP/VPA nerve conduit alone,C group were treated with autologous nerve transplantation,and D group were treated with silicone tube connecting.The sciatic nerve function index(SFI)was detected every 2weeks after operation.The gastrocnemius muscle wet weight was detected every 4 weeks.Three months later,the nerve muscle electrophysiology,histology and transmission electron microscope observation were used.Results:The recovery of motor function in the A group was the fastest among all the four groups(P<0.05),the result of gastrocnemiusmuscle wet weight test in A group was better than that in B and D groups(P<0.05).Conduction velocity and axon counts of Sciatic nerve in A group were better than those of B and D groups(P<0.05).The regenerative sciatic nerve fibers in A group,close to the normal nerve tissue,were much denser than those in B and D groups,and with less demyelination and vacuolar changes of Schwann cells.Conclusion:The use of n-HAP/PRGD/PDLLA/VPA composite materials nerve catheters with local injection of pHVEGF16 in treatment of rat sciatic nerve defect presented a good restoration result,which indicated the significant effect of the composite material nerve catheter on nerve regeneration and vascularization.