Simvastatin对大鼠坐骨神经crush损伤修复作用研究

目的：探讨他汀类（statins）药物Simvastatin在大鼠坐骨神经损伤修复中的作用及可能的作用机制。方法：制作SD大鼠标准坐骨神经钳夹损伤（crush）模型后,分别予Simvastatin和溶媒对照干预2周。手术前后不同时间点进行趾展功能指数测定、神经电生理学、血脂水平、血清IL-6检测和组织学评价。结果：Simvastatin干预组与对照组比较,趾展功能指数在术后5d和8d显著增大（P〈0．05）,足趾展开速度快;2周肌肉复合动作电位幅度高,4周神经传导速度快;组织学显示有髓神经纤维数量多,髓鞘厚,排列相对整齐。各组手术前血脂水平无差异,手术后2周均有不同程度的降低,但Simvastatin干预组总胆固醇降低程度最轻,与对照组比较有显著差异（P〈0．05）;Simvastatin干预组手术后5d,血清IL-6水平明显低于对照组（P〈0．05）。结论：本研究发现,Simvastatin可能通过抑制免疫炎症反应,维持神经损伤后胆固醇的平衡,促进大鼠坐骨神经损伤的修复和再生。

The effect of simvastatin on the regeneration of sciatic nerve with crush injury in rats

Aim: To explore the effect of Simvastatin on the regeneration of sciatic nerve with crush injury in rats. Methods: Animals were randomized into the following experimental groups: Simvastatin-treated, vehicle and sham-operated groups. Sciatic nerves with crush injury were performed. After surgery, the functional evaluation of nerve recovery, electrophysiologic assessment, histological assessment, serum IL-6 and lipid were performed. Results: The toe spread index of Simvastatin-treated rats after operation was higher significantly than vehicle rats at 5 d and 8 d (P<0.05). CMAP was higher and NCV was faster (P<0.05). The serum IL-6 at 5 d of post-operation was significant lower (P<0.05). Total serum cholesterol of Simvastatin-treated animals was higher than that of other animals (P<0.05) at 2 weeks of post-operation. The histological analysis showed that the numbers of myelinated axons and the thickness of myelin sheath of Simvastatin-treated crush injury animals at 4 weeks of post-operation were more than that of vehicle animals. Conclusion: The present study showed that Simvastatin could promote the regeneration of the sciatic nerve after crush injury in rats, partly through inhibiting immune and inflammatory responses and making the balance of serum cholesterol during these processes.