碳纳米管增强型天然复合材料神经导管修复大鼠副神经缺损*☆◆

背景：近年来，纳米技术在组织重建领域的应用研究十分活跃。碳纳米材料应用于骨组织修复的相关报道较多，但应用于周围神经系统修复的报道较少。 目的：应用功能性修饰的碳纳米管作为增强成分改善几丁糖/胶原复合材料神经导管的理化和生物性能，探讨以功能性修饰的碳纳米管增强型复合材料神经导管修复周围神经缺损的疗效。 设计、时间及地点：同体自身对照动物实验，于2005-02/2006-11在上海交通大学医学院口腔组织工程实验室(上海市口腔重点实验室)和上海交通大学薄膜与微细技术实验室(教育部重点实验室)完成。 材料：将碳纳米管与2%的酸溶性几丁糖溶液及胶原按一定比例充分混合，涂覆在模具上，经红外加热成型并达到预期厚度后，干燥脱模制备碳纳米管增强型复合材料导管。以不含碳纳米管的几丁糖/胶原复合材料导管为对照材料。 方法：成年健康雄性Sprague-Dawley大鼠80只，制备4 mm副神经缺损，实验材料组和对照材料组分别应用相应神经导管进行修复。自体神经移植组将切除的神经原位吻接于断端，空白对照组则仅将神经切除掉2 mm，不做处理。左侧为实验侧，右侧为正常对照侧。 主要观察指标：通过神经电生理学、肌肉功能及组织学检测手段对其修复效果进行评价。 结果：应用碳纳米管增强型复合材料神经导管可有效地重建副神经缺损大鼠斜方肌的运动功能。术后再生神经电生理与组织学指标检测结果与自体神经移植的疗效相当，部分指标结果超过自体神经移植。 结论：碳纳米管增强型复合材料神经导管是桥接修复周围神经的理想材料。 关键词：周围神经；碳纳米管；几丁糖；胶原；神经导管 doi:10.3969/j.issn.1673-8225.2009.47.006

Peripheral nerve regeneration using carbon nanotubes enhanced chitosan/collagen composite nerve conduit

BACKGROUND: Nanotechnology has widely used in tissue engineered reconstruction in recent years. Most reports are concerning carbon nanomaterials in bone reparation, but the study of peripheral nerve regeneration is poorly understood. OBJECTIVE: To improve the physical, chemical and biological properties of chitosan/collagen composite nerve conduit with functionalized carbon nanotubes, in addition, to investigate the therapeutic effect of this novel material. DESIGN, TIME AND SETTING: The same body controlled experiment of animals was performed at the Tissue Engineering Laboratory and The Key Laboratory of Thin Film and Microfabrication Technology, Shanghai Jiao Tong University from February 2005 to November 2006. MATERIALS: The carbon nanotubes were mixed with 2% chitosan solution, coated on the die to prepare chitosan/collagen composite nerve conduit with functionalized carbon nanotubes. The chitosan/collagen tubes were served as controls. METHODS: A total of 80 male adult-rats were prepared a 4 mm accessory nerve defects models, and repaired by nerve conduit in the experimental material and control material groups. In the auto nerve grafts group, the removed nerve was connected to the broken end. In the blank control group, there was no other treatment except removing 2 mm nerves. The left sides were served as experimental sides and the right sides as within-subject controls. MAIN OUTCOME MEASURES: The repairing outcomes were measured by electrophysiological, myophysiological, and histological measurements. RESULTS: The accessory nerve defects were repaired in a rat model using carbon nanotubes in chitosan/collagen-based composite nerve conduit. As time passed after the surgery, good results of the electrophysiological, myophysiological and histological measurements were achieved, which were similar or superior to those of the nerve autografts. CONCLUSION: The carbon nanotubes in chitosan/collagen-based composite can be an ideal candidate for peripheral nerve regeneration.