丙酸睾酮对大鼠坐骨神经损伤的治疗作用

Therapeutic effect of testosterone propionate on rat injuried sciatic nerve

目的探讨雄激素丙酸睾酮(TP)对坐骨神经损伤的治疗作用及其机制。方法雄性Wistar大鼠60只,随机等分为实验(TP)组(雄激素治疗组)和对照组(生理盐水治疗组),每组30只。建立坐骨神经离断后缝合外膜的损伤模型,分别在术后第4周、12周比较实验组与对照组运动神经传导速度(MNCV)恢复率和腓肠肌复合动作电位波幅(CMAP)恢复率;取损伤远端神经,观察再生神经的组织学变化;透射电镜观察超微结构变化;计算再生有髓神经纤维计数恢复率。结果术后第4周,TP组MNCV恢复率为(26.74±6.54)%,CMAP恢复率为(28.58±4.49)%,对照组MNCV恢复率为(19.71±4.34)%,CMAP恢复率为(18.95±5.51)%,2组比较差异有统计学意义(P<0.05);术后第12周,TP组MNCV恢复率为(54.31±12.89)%,CMAP恢复率为(71.24±4.05)%,对照组MNCV恢复率为(40.23±10.00)%,CMAP为(62.95±4.89)%,2组比较差异有统计学意义(P<0.05);再生有髓纤维计数恢复率术后第4周TP组为(51.67±9.32)%,对照组为(34.04±10.86)%,差异有统计学意义(P<0.05);术后第12周TP组为(84.03±3.84)%,对照组为(75.13±6.58)%,差异有统计学意义(P<0.05)。术后第4周、12周实验组再生神经纤维较对照组髓鞘致密,排列规则。结论TP能促进周围神经再生和生理功能恢复。

Aim： To explore the therapeutic effect of testosterone propionate on injured sciatic nerve and its mechanism. Methods： A total of 60 adult male Wistar rats were randomly divided into two groups：test group （testosterone propionate-treatment group, TP group） and control group （physiological saline-treatment group, control group）, 30 rats in each group. The sciatic nerve of rats was transected and sutured epineurium. According to the observing periods for 4 and 12 weeks,recovery rate of the complex muscular action potential（CMAP） and motor nerve conduction velocities （MNCV） of test group and control group were measured. Specimens in the distal ends of regenerated nerves were sectioned histologically to observe the histomorphologic changes under light microscope and the uhrastructure changes under electronic microscope. Quantitative analysis of recovery rate of myelinated fiber populations was performed. Results： At 4 weeks MNCV and CMAP of TP group were （26.74 ±6.54）% and （28.58 ±4.49）% , those of control group were （ 19.71 ±4.34）% and （18.95 ± 5.51 ）%, and there were statistical differences between two groups （P 〈 0, 05）. At 12 weeks, MNCV and C MAP of TP group were （54.31 ± 12.89 ） % and （ 71.24 ± 4.05 ） % , those of control group were （ 40.23 ± 10.00） % and （62.95 ±4.89）% , and there were statistical differences between two groups （P 〈0.05）. Quantitative analysis of the recovery rate of myelinated fiber population was （51.67 ±9.32）% at 4 weeks in TP group, （34.04 ± 10.86）% in control group, （84.03 ± 3.84）% at 12 weeks in TP group, （75.13 ± 6.58 ）% at 12 weeks in control group, and the difference between two groups were all significant statistically （ P 〈 0.05 ）. The fibers in TP group were more regular and homogeneous and the myelin sheaths were thicker than that in control group. Conclusion ： TP could effectively promote the regeneration of peripheral nerves and improve the restoration of physiologic functions of regenerating nerve fibers after nerve injury.