Changes in myelin sheath and axon of spinal cord in X irradiation injured rats

Objective To investigate the X irradiation effect on the myelin sheath and axon of the spinal cord. Methods 60 Wistar adult rats receiving hemisection in the thoracic spinal cord were made into models of spinal injury.Among these rats,30 in the test group received X irradiation of 35 Gy the day after operation, while 30 in the control group only received hemisecton. Operative spinal cord was subjected to immunohistochemistry and hypermicroscopic observation. Results In the test group, injury to the myelin sheath of the upper and lower lesion and the number of neurofibrotic positive axon increbsed. In the control group the number of myelin sheath below the injured section decreased. Under electronic microscope,demyelination was found in the spinal cord and new born tiny neurofibrotic tracts were seen below the lesion. Conclusions X irradiation can make spinal cord demyelinate and promote the increase of neurofibrotic positive axon.