聚乳酸和聚羟基乙酸共聚物复合膜修复坐骨神经损伤

背景：聚乳酸和聚羟基乙酸复合膜具有良好的生物相容性，稳定的机械强度，无毒副作用，可控的降解速率等特点。 目的：观察聚乳酸和聚羟基乙酸共聚物膜对大鼠坐骨神经损伤的修复作用。 方法：手术显露36只Wistar大鼠坐骨神经，随机分成3组：假手术组游离坐骨神经后不作任何处理，对照组切断坐骨神经后行神经断端直接吻合，实验组于神经吻合断端包裹聚乳酸和聚羟基乙酸共聚物膜。 结果与结论：①神经电生理学检测：术后4，6周神经传导速度及波幅比较，对照组<实验组<假手术组(P均<0.05)。②组织学检测：对照组神经与周围组织粘连严重，实验组吻合口光滑平整，聚乳酸和聚羟基乙酸共聚物膜明显降解吸收，与周围组织无粘连，对照组有髓神经数量较假手术组、实验组明显减少，且轴突再生率和再生轴突成熟度较低。③辣根过氧化物酶逆行示踪检测：对照组被辣根过氧化物酶标记的阳性有髓神经纤维数量较假手术组、实验组明显减少。表明聚乳酸和聚羟基乙酸共聚物膜能减轻神经术后粘连，促进神经再生。

Polylactic acid-polyglycolic acid membrane for repairing sciatic nerve injuries in rats

BACKGROUND:Polylactic acid (PLA)-polyglycolic acid (PLGA) membrane has good biocompatibility, stable mechanical strength, non-toxic side effects and controllable degradation rate. OBJECTIVE:To investigate the repair effect of PLA-PLGA membrane on the injury of sciatic nerve in rats. METHODS:Health 36 male Wister rats were selected to expose the sciatic nerve after surgery and randomly divided into sham operation group, control group and experimental group. Rats in the sham operation group received no treatment after the free of sciatic nerve; those in the control group underwent direct end to end nerve anastomosis; while those in the experimental group were wrapped by PLA-PLGA membrane after the end to end nerve anastomosis. RESULTS AND CONCLUSION:①Electrophysiology detection: The nerve conduction velocity and wave amplitude in the control and experimental groups were better than those in the sham operation group, and the control group was better than the experimental group (P < 0.05). ②Histological detection: Adhesion between nerve in the control group and surround tissues was severe. The anastomosis in the experimental group was smooth and flat, besides, PLA-PLGA membrane was degenerated and absorbed obviously, and no adhesion with surround tissues. The number of myelinated nerve in the control group was obviously decreased, compared with the sham operation and experimental groups, moreover, the regeneration ratios and degree of maturity of neural axis was lower. ③Horseradish peroxidase retrograde tracing: The number of positive myelinated nerve fiber marked by horseradish peroxidase of the control group was decreased significantly than that of the other two groups. These results suggest that PLA-PLGA membrane can prevent neural adhesion after surgery and promote nerve regeneration.