Experimental study on regeneration of ascending tract after spinal cord injury with predegenerated peripheral nerve graft and NGF infusion

摘要

Objective: To explore the effects of predegenerated peripheral nerve graft (PPNG) combined with nerve growth factor (NGF) infusion on ascending sensory tract regeneration after spinal cord injury. Methods: Fifty female SD rats were randomly divided into 5 groups. Group A was treated with PPNG and NGF infusion, group B with PPNG, group C with NGF infusion, group D and group E were blank and normal control, respectively. Horseradish peroxidase-labled (HRP) tracing method was employed to evaluate the regeneration of injured nerves after 8 weeks. The extent of regeneration in and beyond the nerve graft was determined by counting the number of HRP-labeled fibers intersecting imaginary lines perpendicular to the axis of the graft and cord. For the sake of convenience, according to the relation of the PNG and spinal cord, 6 model zones were divided, including caudal of spinal cord, caudal transition zone, caudal zone in graft, rostral zone in graft, rostral transition zone and rostral of spinal cord. Results: On the transverse section of caudal zone in graft, rostral zone in graft, rostral transition zone, the fibers in group A were significantly higher than that in group B and C (P < 0. 05). Conclusion: PPNG combined with NGF may significantly promote the regeneration of ascending long tract after spinal cord injury. The regenerative fibers can penetrate the 2 graft-host interface scars.