Biotinylated dextran amine tracing of nerve tracts determines regeneration of corticospinal tracts after neural stem cell transplantation

摘要

We investigated regeneration of the corticospinal tract and rearrangement of corticospinal nerves after spinal cord injury by biotinylated dextran amine (BDA) nerve tract tracing after neural stem cell transplantation.Neural stem cell transplantation increased motor function scores of rats at 3 weeks after spinal cord transection injury at the thoracic 10 segment.A proportion of BDA-labeled corticospinal tract regenerated through the spinal cord injury site at 12 weeks after transplantation.Electron microscopy revealed that the regenerated BDA-labeled nerve terminals formed new synaptic connections with neurons at the distal end of the injured site.These findings indicate that BDA nerve tract tracing effectively provides anatomic and morphological evidence of recovery after spinal cord injury.