部分脱乙酰甲壳质生物套管小间隙桥接修复周围神经损伤:免疫组织化学观察

Using a deacetylated chitin biological tube for bridging peripheral nerve defect with a small gap: An immunohistochemical observation

目的:神经断端保留小间隙的静脉桥接模拟神经外膜形成神经再生室,为周围神经再生创造了良好的生理环境,从而保证神经束的良好对合。实验采用部分脱乙酰甲壳质作为套管材料,用小间隙桥接方法修复坐骨神经损伤,观察套管内的神经再生情况,并与传统外膜缝合法进行比较。方法:实验于2001-01/2002-10在北京大学人民医院创伤骨科实验室完成。①主要材料:实验所用中空圆柱形套管为北京大学人民医院与中国纺织科学院共同发明的一种部分脱乙酰甲壳质生物套管(专利号:01136314.2)。实验中所用套管尺寸为:管长4 mm,壁厚0.1 mm,内径1.5 mm。②实验动物:健康成年雄性SD大鼠20只,随机分成2大组,每组10只,每一大组全部10只动物的左腿坐骨神经为一组,右腿坐骨神经为另一组,每组10根坐骨神经。另取5只同样大鼠双侧坐骨神经未做处理作为正常对照组。③实验方法:外膜原位缝合组:切断坐骨神经,显微镜下神经外膜原位缝合;生物套管小间隙原位桥接组:切断坐骨神经,显微镜下小间隙套管桥接;断端旋转180°外膜缝合组:切断坐骨神经,显微镜下远端旋转180°后,神经外膜缝合;断端旋转180°生物套管小间隙桥接组:切断坐骨神经,显微镜下远端旋转180°后,小间隙套管桥接。④实验评估:术后第7,14,21,28,42天取坐骨神经,进行免疫组织化学染色及观察。结果:再生神经延套管中央走行,7 d时已有部分纤维通过2 mm间隙,14 d时有髓纤维数量明显多于近端。21 d后,套管组与原位外膜组新生有髓神经纤维数相近。再生纤维胞核数量较多,髓鞘纤细。套管结构完整。结论:此种部分脱乙酰甲壳质生物套管内的再生神经连续、整齐,髓鞘完整,其神经再生情况好于传统外膜缝合法。

AIM： Bridging the small gap between venous nerve stumps can stimulate epineurium and form nerve regeneration chambers, providing good physiological environment for pedpheral nerve regeneration and ensure anneal of nerve tract. This study was to observe the regeneration process of peripheral nerve in a deacetylated chitin tube by a small gap bridging to repair the sciatic nerve defects, and compare with the effect of traditional epineurium suture. METHODS： The experiment was carried out in the Laboratory of Trauma and Orthopedics at Peking University People＇s Hospital from January 2001 to October 2002.（1）Deacetylated chitin biological tubers （patent number： 01136314.2）, which were hollow and cylinder, were invented by Peking University People＇s Hospital and China Textile Academy, with a size of 4 mm tube length, 0.1 mm wall thickness and 1.5 mm inner diameter. （2）Twenty healthy adult male SD rats were randomly divided into 2 groups （n =10）, and then every rat was allocated into left sciatic nerve set and right sciatic nerve set. Another 5 rats without any interventions were taken as normal control group.（3）Sciatic nerves of SD rats were cut off and received epineurium suture in situ, small gap bridging in situ, epineurium suture with distal stump rotated 180°, and small gap bridging with distal stump rotated 180°, respectively.（4）Sciatic nerves were harvested on days 7, 14, 21, 28, 42 postoperatively for immunohistochemical observation. RESULTS： The regenerating fibers elongated in the center part of the tube and some fibers already passed the 2-mm gap on the 7^th day. The number of the myelinated fibers in the distal stump was more than that in the proximal on the 14^th day. The tube group and the epineurium in situ group had the approximate number of myelinated fibers on the 21^st day, which possessed more cells and thinner myelin. The tuber still maintained the complete structure. CONCLUSION： The regenerated nerves are successive and well-arranged in the deacetylated chitin biological tube, which is superior to traditional epineurium suture.