脱细胞动脉复合耳脑胶修复兔面神经缺损的实验

Effect of acellular artery combined with medical aural and encephalic glue in repair of rabbit facial nerve defects

目的探索采用脱细胞动脉复合耳脑胶修复面神经缺损的可行性。方法 10只新西兰大白兔用于获取脱细胞动脉,15只新西兰大白兔随机分为3组:脱细胞动脉复合耳脑胶组、脱细胞动脉组、自体神经对照组。手术制备面神经上颊支1 cm长缺损模型,分别采用各组神经移植物桥接修复面神经缺损断端。术后1周、4周、12周对实验动物进行大体观察;术后12周取材,对各组神经移植物及周围组织进行大体观察,取材进行组织学检测,统计分析各组有髓神经纤维密度、髓鞘厚度及轴突直径。结果动脉脱细胞后HE染色和Masson染色未见细胞成分残留。术后1周、4周时,各组动物术侧口角仍无动度,术区无明显炎症反应及肿胀;术后12周时脱细胞动脉复合耳脑胶组口角对称性差于自体神经对照组,但优于脱细胞动脉组。术后12周取材时,脱细胞动脉组较其他两组的神经移植物塌陷程度明显严重;脱细胞动脉复合耳脑胶组的有髓神经纤维密度[(12 608.61±163.48)n/mm^2]、髓鞘厚度[(680.16±114.23)nm]和轴突直径[(5.03±0.42)μm]小于自体神经对照组的有髓神经纤维密度[(18 573.93±68.65)n/mm^2]、髓鞘厚度[(1165.7±184.64)nm]和轴突直径[(5.52±0.28)μm],但大于脱细胞动脉组的有髓神经纤维密度[(9 571.34±131.45)n/mm^2]、髓鞘厚度[(204.13±70.65)nm]和轴突直径[(4.61±0.55)μm](P均<0.05)。结论采用耳脑胶可以改善脱细胞动脉植入体内后的塌陷问题,更好地促进神经再生。

Objective To explore the feasibility of the reconstruction of transected facial nerves with rabbit allogeneic decellularized artery combined with medical aural and encephalic （EC） glue. Methods Ten New Zealand white rabbits were used to obtain allogeneic decellularized artery, which were detected by HE staining and Masson staining. Fifteen New Zealand white rabbits were randomly divided into 3 groups - the decellularized artery-EC glue group, the decellularized artery group and the autologous nerve control group. The fifteen rabbits were used to establish the model of 10 mm gap on buccal branch of the facial nerve, and three kinds of nerve grafts mentioned above were used to repair the gaps. The animals were observed generally at 1, 4, 12 weeks after operation. At 12 weeks after surgery, the nerve grafts and surrounding tissues in each group were generally observed. Then, the nerve grafts were evaluated with histological examination, and the statistical analysis of the density of myelinated nerve fibers, the thickness of the myelin sheaths and the diameter of the axons were compared between the three groups. Results After decellularization, no cellular components but extracellular matrixc （ECM） collagen fibers remained in fabricated allogeneic decellularized artery confirmed by HE staining and Masson staining. No obvious inflammation response and swelling were observed at the operation side at 1 week, 4 weeks after operation with no free movement of the lips at the surgical side. At 12 weeks after surgery, the symmetry of rabbits’ mouths in the decellularized artery-EC glue group restored less than that in the autologous nerve control group, but greater than that in the decellularized artery group. The nerve grafts in the decellularized artery group collapsed compared with the other two groups. The density of myelinated fibers （12 608.61±163.48 n/mm^2）, the thickness of myelin sheaths （680.16±114.23 nm） and the diameter of the axons （5.03±0.42 μm） in the decellularized artery-EC glue group were less than the density of myelinated fibers （18 573.93±68.65 n/mm^2）, the thickness of myelin sheaths （1 165.7±184.64 nm） and the diameter of the axons （5.52±0.28μm） in the autologous nerve control group, but greater than the density of myelinated fibers （9 571.34±131.45 n/mm^2）, the thickness of myelin sheaths （204.13±70.65 nm） and the diameter of the axons （4.61±0.55 μm） in the decellularized artery group （P 〈 0.05, respectively）. Conclusion Allogeneic decellularized artery combined with EC glue is a useful method to reduce the collapse after decellularized artery implantation and to promote the nerve regeneration effectively in repairing of rabit facial nerve defects.