Abstract
Spatio/Temporal Regeneration of Oligodendrocyte Progenitor Cell after Spinal Cord Injury in Adult RodentsDi Wu1, Sei Shibuya1, Osamu Miyamoto2, Toshifumi Itano2Departments of Orthopaedic Surgery1 and Neurobiology2, Faculty of Medicine, Kagawa University In adult mammals, differentiation and regeneration of oligodendrocyte progenitor cells do happen after SCI. In this study we analyzed the NG2 expression after SCI, which is the specific marker for oligodendrocyte progenitor. SD rats had a laminectomy at Th11-12, spinal cord contusion was created by compression with 30 g of force for 10 min. Animals were examined at 24 h and 1, 4, 8 and 12 weeks after injury. 20-μm-thick frozen sections were prepared. Immunohistochemical staining was performed using antibody to NG2. At 4 weeks after injury, NG2 (+) bipolar oligodendrocyte progenitor with arborizing processes had spread throughout the white matter from below the pial surface. At 8 weeks after injury, NG2 expression reached the peak which was 5-fold greater than that in control group. NG2 expression was also observed in the gray matter around the central canal, and was especially strong around the ependymal cells at 8 weeks after the injury which was 4-fold greater than that in the control group. The present study showed that oligodendrocyte progenitor cells divide and migrate from subpial astrocytes. This may be the special mechanism in neural repair and regeneration after SCI in adult mammals, which is different from that in embryonic stage. [Jpn J Physiol 54 Suppl:S246 (2004)]
