Neural Cell Apoptosis and the Expression of Caspase-3,Apoptosis-inducing Factor after Acute Spinal Cord Injury

Objective To study the apoptosis of the neural cells and the changes of caspase-3,AIF′s expression after acute spinal cord injury in rats.Methods The spinal cord injury of the healthy adult SD rats(78)were induced with Nystrom’s way by the moderate compression at the level of T8 and T9 spinal cord.HE method was used to detect the pathologic change of spinal cord.The expression of caspase-3 and AIF was detected by immunohistochemical study.Besides,by using the DUTP nick and labeling(TUNEL)methods which was mediated by terminal deoxynucleotidyl transferase to detect the level of the apoptosis of neural cells.Results There was less expression of AIF,caspase-3 and TUNEL-positive cells in normal and sham operated spinal cord as detected by immunohistochemical study.The number of positive cells of AIF increased clearly 1 day and then reached a peak,but it was rarely seen 5 days after spinal injury.The expression of caspase-3 increased obviously 8 hours after spinal injury,then reached a peak 3 days after spinal injury,but it decreased 7 days after spinal injury.The number of positive cells of TUNEL also increased obviously 8 hours after spinal injury,and then reached a peak on 3 day,and also decreased 7 days after spinal injury.Conclusion There is apoptosis of the neural cells after acute spinal cord injury,and AIF,caspase-3 may be involved in the regulation of the apoptosis of neural cells after acute spinal cord injury.