目的 观察内源性 Spastin 蛋白在大鼠坐骨神经损伤后再生过程中的表达变化，探讨其在周围神经再生过程中的作用和意义。 方法 取成年雄性 SD 大鼠 36 只，随机分为实验组（n=30）和假手术对照组（n=6），实验组建立坐骨神经挤压损伤模型，对照组仅暴露坐骨神经。实验组分别于术后 1、3、7、14、28 d（n=6），假手术组于术后 7 d 取大鼠坐骨神经相应节段的 L4~6 脊髓组织，采用实时荧光定量 PCR 检测 Spastin mRNA 相对表达量，Western blot 检测 Spastin 蛋白表达；并取损伤远端 5 mm 处神经组织，通过透射电镜观察坐骨神经远端轴突的超微结构变化。 结果 两组大鼠 L4~6 节段脊髓组织中 Spastin 蛋白表达和基因表达变化趋势基本一致。实验组 Spastin 蛋白和基因表达量呈先下降后逐渐上升的趋势，于术后 7 d 降至最低，28 d 时达初始水平。其中实验组术后 3、7、14 d Spastin 蛋白和基因表达量显著低于假手术对照组（P<0.05）；术后 1、28 d 与假手术对照组比较差异无统计学意义（P>0.05）。实验组术后 3、7、14 d Spastin 蛋白和基因表达量显著低于术后 1 d 和 28 d（P<0.05），术后 1 d 和 28 d 比较差异无统计学意义（P>0.05）。透射电镜观察发现实验组术后 1、3、7 d，坐骨神经损伤远端髓鞘严重破坏；术后 14 d 雪旺细胞增生；术后 28 d 可见大量有髓神经纤维，接近正常形态。 结论 内源性 Spastin 蛋白在坐骨神经损伤后再生过程中出现了表达变化，提示 Spastin 可能在周围神经损伤后的再生过程中起着一定作用
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