Wang Shenguo, Cai Qing, Hou Jianwei, Bei Jianzhong, Zhang Tao, Yang Jian, Wan Yuqing
Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
J Biomed Mater Res A. 2003 Sep 1;66(3):522-31. doi: 10.1002/jbm.a.10008.
In this study, nerve guides composed of poly(D,L-lactide) (PDLLA) were fabricated and used in the repair of transected sciatic nerves (15-mm gaps) of rats. Nerve guides with a two-ply structure (inner layer dense, outer layer microporous) were prepared by controlling the solvent evaporation rate. Then basic fibroblast growth factor (bFGF) was embedded in the inner layer of the nerve guides. Thus the inner dense layer not only could prevent the ingrowth of fibroblast and avoid the outgrowing nerve cable, but it also could retain the released bFGF in the guide lumen. The outer porous layer allowed vascular ingrowth and the diffusion of essential nutrients into the guide lumen. The data show that by using this nerve guide, the transected 15-mm sciatic nerve was regenerated successfully within 4 months. The recovery of function of the regenerated nerves was significantly accelerated by bFGF, as indicated by an electrostimulation test and histologic assays. In addition, the bFGF retained its bioactivity during embedding and continuously was released from the matrix, as confirmed by the results of both the dorsal root ganglia (DRG) and the Schwann cell culture in the presence of PDLLA matrix containing bFGF. The released bFGF enhanced the ability of the nerve fibers to sprout from dorsal root ganglia, and it accelerated the proliferation of Schwann cells.
在本研究中，制备了由聚（D，L-丙交酯）（PDLLA）组成的神经导管，并将其用于修复大鼠坐骨神经横断伤（15毫米间隙）。通过控制溶剂蒸发速率制备了具有双层结构（内层致密，外层微孔）的神经导管。然后将碱性成纤维细胞生长因子（bFGF）包埋在神经导管的内层。因此，内层致密层不仅可以防止成纤维细胞向内生长并避免神经束向外生长，而且还可以将释放的bFGF保留在导管腔内。外层多孔层允许血管向内生长并使必需营养物质扩散到导管腔内。数据表明，使用这种神经导管，横断的15毫米坐骨神经在4个月内成功再生。如电刺激试验和组织学分析所示，bFGF显著加速了再生神经功能的恢复。此外，如在含有bFGF的PDLLA基质存在下进行的背根神经节（DRG）和雪旺细胞培养结果所证实的，bFGF在包埋过程中保留了其生物活性，并持续从基质中释放出来。释放的bFGF增强了神经纤维从背根神经节发芽的能力，并加速了雪旺细胞的增殖。
