兔化学去细胞神经桥接大鼠面神经缺损

Repair of rat facial nerve defects with rabbit acellular nerve by chemical extraction

目的探索化学去细胞神经异种移植桥接面神经缺损的可能性。方法用TritonX-100和脱氧胆酸钠制备兔化学去细胞神经,桥接大鼠面神经6mm缺损。术后5个月行神经电生理、面神经运动神经元逆行示踪、再生神经形态学等检测。以大鼠自体神经移植和兔新鲜神经移植为对照。结果化学去细胞异种神经未被宿主排斥和吸收,正常侧/实验侧潜伏期比值为0.663±0.142,实验侧/正常侧波幅比值为0.334±0.032,实验侧/正常侧标记面神经运动神经元比值为0.293±0.023,神经移植段及移植远段有大量再生神经纤维且超微结构正常。与大鼠自体神经移植比较差异无统计学意义(P>0.05),而新鲜神经异种移植被宿主排斥和吸收。结论化学去细胞神经异种移植可能是修复面神经缺损的一种很有前途的方法。

OBJECTIVE To explore the possibility to bridge the facial nerve defects by xenogeneic acellular nerve. METHODS Sixty Wistar rats were randomly and equally divided into three groups： xenogeneic acellular nerve graft, nerve autograft and xenogeneic fresh nerve graft. The inferior buccal branch of the left facial nerve of rats were exposed and 6 mm long segment of the nerve was removed, and replaced by above-mentioned three kinds of nerve grafts respectively. The acellular nerve was chemically extracted by the detergents of 30 ml/L TritonX-100 and 40 g/L deoxycholate sodium. The recovery of function and morphology of nerve regeneration was observed by using electromyography, horseradish peroxidase retrograde trace, methylene blue staining, transmission electron microscope respectively at the 5th month after operation. RESULTS In the xenogeneic acellular nerve graft group, no excessive signs of rejected and absorbed reaction could be observed in the acellular segments. The latency ratio of nerve-muscle action potential on normal side / experimental side was 0.663±0.142; The amplitude ratio of nerve-muscle action potential on experimental side / normal side was 0.334 ± 0.032; The ratio of the labeled facial motor neurons on experimental side / normal side was 0.293 ± 0.023. The regenerated nerve fibers had normal morphological and structural characters under transmission electron microscope. The results in the xenogeneic acellular nerve graft group were similar to those of the nerve autograft group（P〉0.05）. In the xenogeneic fresh nerve graft group, the xenogeneic nerve segment was rejected and absorbed by the recipient. CONCLUSION Xenogeneic acellular nerve could sustain facial nerve regeneration, and may be a substitute to autograft for repairing facial nerve defects.