神经细胞外基质材料制备及修复周围神经缺损的实验研究

目的 :制备一种新型天然神经细胞外基质材料 ,通过动物实验研究 ,探讨其修复周围神经干节段性缺损的可行性。方法 :采用NaOH消蚀法 ,制备家兔坐骨神经细胞外基质材料 ,行扫描电镜观察及生物相容性实验 ,用于桥接修复家兔坐骨神经节段性缺损并以自体神经修复作为对照 ,术后通过肌电图检测、再生神经纤维组织学观察等方法 ,证实该支架可有效地引导和促进神经纤维再生。结果 :(1)经NaOH消蚀处理的坐骨神经组织 ,其细胞成分被完全消蚀掉 ,神经膜管保持原有的构筑特征 ;无明显排异反应并可降解吸收。 (2 )该材料和自体神经移植修复周围神经干节段性缺损在电生理和组织结构的恢复方面经统计学处理无显著性差异 (P >0 .0 5 )。结论 :此方法制备的细胞外基质材料可有效地桥接修复周围神经干节段性缺损 ,为其临床应用奠定实验基础。

Preparation of the nerve extracellular matrix material and the experimental study on the repairing of nerve segmental defects

Objective:To prepare a new nerve extracellular matrix(ECM)for the recovery of segmental defects of the peripheral nerve in rabbits. Methods:The materials were made by immersing the samples of sciatic nerve into NaOH aqueous solution and cleaned by ultrasonic wave(USW),then observed it by scanning electron microscope(SEM).The materials were implanted into the muscles of rabbits for the study of biocompatibility, and then bridged to repair segmental defects of the peripheral nerve in rabbits. Under light microscope, diameter of myelinated nerve fibers and axis-cylinder in the grafts were examined with HE staining at different postoperative intervals (8 and 16 weeks). In addition, Nerve electrophysiology was recorded at 16 weeks after transplantation. Results:(1) The cellular elements of the sciatic nerve treated with NaOH-maceration were eliminated completely, while the original three-dimensional structure of the endoneurium, perineurium and epineurium were preserved integrately. (2) No significant difference was observedbetween the experiment groups and the control groups ( P >0.05) were checked up. Conclusion:The ECM has a good biocompatibility, which can induce nerve fibers to regenerate. This study provide an experiment foundation for clinical nerve surgery.