ABSTRACT
Objective To investigate the effects of rehabilitation training on the microenvironment for axon regeneration and the possible mechanisms promoting axon regeneration,reconstruction and functional compensation after spinal cord injury (SCI) in beagle dogs.Methods Fifteen beagles were divided into a sham operated group,an SCI model group and a rehabilitation training group.Spinal cord hemi-transection injury was carried out.From the 8th day after SCI,the rehabilitation training group was given treadmill training.All dogs were sacrificed 60 days postinjury and samples were harvested.Chondroitin sulphate proteoglycan (CSPG) expression of astroglial cells around the injured area was observed using an immunofluorescence technique.The expression of glial fibrillary acidic protein (GFAP) and CSPG protein in each group were semi-quantified by Western blot analysis.Axon regeneration was observed by silver staining.Motor function was assessed using modified Tarlov scores.Results In the rehabilitation training group,compared with the model group astroglial production of CSPG was reduced remarkably.Both CSPG expression and axon regeneration were enhanced and functional deficits improved.Conclusions Rehabilitation training can inhibit astroglial production of CSPG,improve the microenvironment for injured axon regeneration,and promote reconstruction and functional compensation after traumatic SCI.