Cai Jie, Peng Xuejun, Nelson Kevin D, Eberhart Robert, Smith George M
Department of Physiology, MS 508, Albert B. Chandler Medical Center, Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky 40536-0298, USA.
J Biomed Mater Res A. 2005 Nov 1;75(2):374-86. doi: 10.1002/jbm.a.30432.
Successful peripheral nerve regeneration is still limited in artificial conduits, especially for long lesion gaps. In this study, porous poly(L-lactide-co-DL-lactide, 75:25) (PLA) conduits were manufactured with 16 poly(L-lactide) (PLLA) microfilaments aligned inside the lumen. Fourteen and 18 mm lesion gaps were created in a rat sciatic nerve lesion model. To evaluate the combined effect of permeable PLA conduits and microfilament bundles on axon growth, four types of implants were tested for each lesion gap: PLA conduits with 16 filaments; PLA conduits without filaments; silicone conduits with 16 filaments; and silicone conduits without filaments. Ten weeks following implantation, regeneration within the distal nerve was compared between corresponding groups. Antibodies against the markers S100, calcitonin gene related peptide (CGRP), RMDO95, and P0 were used to identify Schwann cells, unmyelinated axons, myelinated axons, and myelin, respectively. Results demonstrated that the filament scaffold enhanced tissue cable formation and Schwann cell migration in all groups. The filament scaffold enhanced axonal regeneration toward the distal stump, especially across long lesion gaps, but significance was only achieved with PLA conduits. When compared to corresponding silicone conduits, permeable PLA conduits enhanced myelinated axon regeneration across both lesion gaps and achieved significance only in combination with filament scaffolds. Myelin staining indicated PLA conduits supported axon myelination with better myelin quantity and quality when compared to silicone conduits.
在人工导管中，成功的周围神经再生仍然受到限制，尤其是对于长节段缺损。在本研究中，制备了多孔聚（L-丙交酯-co-DL-丙交酯，75:25）（PLA）导管，其管腔内排列有16根聚（L-丙交酯）（PLLA）微丝。在大鼠坐骨神经损伤模型中制造了14毫米和18毫米的节段缺损。为了评估可渗透PLA导管和微丝束对轴突生长的联合作用，针对每个节段缺损测试了四种类型的植入物：带有16根细丝的PLA导管；没有细丝的PLA导管；带有16根细丝的硅胶导管；以及没有细丝的硅胶导管。植入后十周，比较相应组之间远端神经内的再生情况。分别使用针对标记物S100、降钙素基因相关肽（CGRP）、RMDO95和P0的抗体来识别施万细胞、无髓轴突、有髓轴突和髓磷脂。结果表明，细丝支架增强了所有组中的组织束形成和施万细胞迁移。细丝支架增强了轴突向远端残端的再生，尤其是跨越长节段缺损时，但仅在PLA导管中达到显著水平。与相应的硅胶导管相比，可渗透PLA导管增强了两个节段缺损处有髓轴突的再生，并且仅与细丝支架联合时才达到显著水平。髓磷脂染色表明，与硅胶导管相比，PLA导管以更好的髓磷脂数量和质量支持轴突髓鞘形成。
