壳聚糖导管填充辛伐他汀／泊洛沙姆407水凝胶促进大鼠坐骨神经缺损后运动功能恢复

摘要

目的：探讨壳聚糖导管复合辛伐他汀／泊洛沙姆407水凝胶对大鼠坐骨神经缺损后运动功能恢复的影响。方法选取成年SD大鼠40只，随机分成壳聚糖导管组、壳聚糖导管复合辛伐他汀0 mg水凝胶组、壳聚糖导管复合辛伐他汀0．5 mg水凝胶组和壳聚糖导管复合辛伐他汀1 mg水凝胶组（前2组为对照组，后2组为辛伐他汀治疗组），每组10只，制作左侧坐骨神经10 mm缺损模型，用壳聚糖导管桥接缺损，其内填充不同浓度的辛伐他汀水凝胶。术后4、6、8、10周进行坐骨神经指数检测，术后10周进行神经电生理、荧光金逆行示踪、腓肠肌相对湿重、肌纤维面积百分比和运动终板形态检测，观察神经缺损后运动功能恢复情况。结果术后4、6、8、10周，辛伐他汀治疗组的坐骨神经指数均明显高于对照组（ P＜0．05）；术后10周辛伐他汀治疗组复合肌肉动作电位的峰－峰值、运动神经传导速度、荧光金标记的阳性神经元数量、腓肠肌相对湿重、肌纤维面积百分比和运动终板的恢复均显著优于对照组（P＜0．05）。结论壳聚糖导管复合辛伐他汀／泊洛沙姆407水凝胶能够促进外周神经损伤后的功能恢复。%Objective To investigate effects of simvastatin/pluronic F-127 hydrogel combined with chitosan conduit on motor functional recovery of rats with sciatic nerve defects . Methods A total of 40 adult Sprague-Dawley rats were assigned randomly into four groups:chitosan conduit group and groups of the conduit filled with pluronic F-127 hydrogel containing 0 mg, 0.5 mg, and 1 mg simvastatin ( the first two groups were control groups while the last two groups as simvastatin treated groups ) , with 10 rats in each group.A 10 mm gap was produced in left side of sciatic nerves and then was repaired by the chitosan conduit filled with pluronic F -127 hydrogel containing different doses of simvastatin .At different periods after surgery , the functional recovery was evaluated by sciatic functional index ( SFI ) , electrophysiology , fluoro-gold retrograde tracing , the relative gastrocnemius muscle weight ( RGMW ) , the percentage area of muscle fibers and the morphology of motor endplates . Results At 4, 6, 8, and 10 weeks after surgery , values of SFI in simvastatin treated groups were significantly higher than those in the control groups (P<0.05).Similarly, at 10 weeks after surgery, the peak amplitude and motor nerve conduction velocity of compound muscle action potential (CMAP), number of FG-labled neurons , RGMW, the percentage area of muscle fibers and the morphology of motor endplates in simvastatin treated groups were superior to those in the control groups ( P <0.05 ). Conclusion These findings indicate that filling chitosan conduits with simvastatin/pluronic F-127 hydrogel can improve motor functional recovery in rats .