The Changes in the Expression of CD44 of Rat with Hemisection of Spinal Cord Injury

Objective To investigate the expression changes of CD44 in spinal cord in 3d,7d and 14d following hemisection of spinal cord injury(hSCI).Furthermore,to explore the relationships of CD44 and spinal cord injury.Besides,to offer the morphological datum for the research concerning the spinal cord repair.Methods 20 adult healthy Sprague-Dawley rats were randomly divided into sham-operated control group and day3,day7,day14 spinal cord injury groups.The spinal cords were hemisected between T9 and T10.The spinal cord of every rat was taken out from the rostral and caudal segments of lesioned areas.Then the tissue blocks were made into 25μm frozen sections and the immunohistochemistry ABC method was performed on these sections.We respectively observe and count the number of CD44 positive cells in spinal cord for all groups,and the average OD(optical density) value of immunoreactant were detected with computer image analysis technique.Results CD44 positive products were mainly distributed in extacellular matrix and neurons and neuroglial cells in spinal cord for the control group.The number of CD44 positive cells and its OD value of rostral or caudal part of injury site for the three spinal cord injury groups were all increased(P0.05).Conclusion The increased-expression CD44 may mutually play inhibitory effect on axon regeneration following SCI.