Expression and significance of cathepsin B after acute spinal cord injury / 中国矫形外科杂志

ABSTRACT

[Objective]To study the expression of Cathepsin B,Caspase-3 and to explore the significance of their expression initially after acute spinal cord injury in rats.[Method]The spinal cord injury of the healthy adult SD rats (78) was induced with Nystrom’s way by the moderate compression at the level of T8 and T9 spinal cord. HE methods were used to detect the pathologic change of spinal cord. The expression of Cathepsin B and Caspase-3 were detected by immunohistochemical study. Besides,using the terminal deoxynucleotidyl transferase mediated DUTP nick and labeling (TUNEL) methods to detect the level of the apoptosis of neural cells.[Result]There were few expressions of Cathepsin B, Caspase-3 and TUNEL positive cells in normal and sham operated spinal cord as detected by immunohistochemical study. The number of positive cells of Cathepsin B increased clearly at 3 days,reached a peak at 5 days,and was constant at 7 days after injury. While the expression of Caspase-3 increased obviously at 8 hours,got to a peak at 3 days,and was lowest at 7 days. And the number of positive cells of TUNEL also increased obviously at 8 hours,got to a peak at 3 days,and was lowest at 7 days. There were significance differences of morphological and position of positive cells between Cathepsin B and Caspase-3 or Tunel. [Conclusion]Caspase-3 protein expressions are enhanced in combination with neuronal apoptosis,while Cathepsin B may involve in the secondary injury by inflammatory cells after acute spinal cord injury.