Weinberg E L, Raine C S
Brain Res. 1980 Sep 29;198(1):1-11. doi: 10.1016/0006-8993(80)90339-x.
Newly transected or denervated segments of isogeneic rat tibial nerve were implanted into the rat midbrain and sampled at weekly intervals up to 6 weeks post-operation. By 3 weeks, the peripheral nervous system (PNS) grafts were well-vascularized and contained Schwann cells, axons associated with Schwann cell processes, and macrophages. From 3 to 6 weeks, many axons within both the fresh and predegenerated grafts were myelinated by Schwann cells. The nerve fiber arrangement within the implant was similar to that of regenerating peripheral nerve in situ. The central nervous system (CNS) border of the implant was clearly demarcated by a rim of astrocytes behind which was a layer of regenerating oligodendrocytes and axons. Extending from the CNS margin were radial bridges of astroglial tissue which apprarently guided regenerating axons into the implant. Between the CNS and the PNS implant, abundant collagen deposition was present. The findings suggest that regenerating CNS axons grow via astroglial bridges into transplanted PNS tissue and are capable of stimulating the implanted Schwann cells to form myelin. Even Schwann cells deprived of axonal contact for prolonged periods were still capable of PNS myelin formation.
将同基因大鼠胫神经新横断或去神经支配的节段植入大鼠中脑，并在术后每周取样，直至术后6周。到3周时，周围神经系统（PNS）移植物血管化良好，包含施万细胞、与施万细胞突起相关的轴突和巨噬细胞。在3至6周期间，新鲜和预变性移植物中的许多轴突都被施万细胞髓鞘化。植入物内的神经纤维排列与原位再生的周围神经相似。植入物的中枢神经系统（CNS）边界由一层星形胶质细胞清晰界定，其后方是一层再生的少突胶质细胞和轴突。从CNS边缘延伸出星形胶质组织的放射状桥，显然引导再生轴突进入植入物。在CNS和PNS植入物之间，有大量胶原沉积。这些发现表明，再生的CNS轴突通过星形胶质桥生长到移植的PNS组织中，并能够刺激植入的施万细胞形成髓鞘。即使长时间没有轴突接触的施万细胞仍能够形成PNS髓鞘。
