Neuroserpin Expressed In Rat Spinal Cord Continuous Compression Injury Research

Object To observe the expression of Neuroserpin in the condition of sustained compression of spinal cord and its relationship between microglia, tPA and neuronal apoptosis.Measure We established an animal model in rat for simulating compression of spinal cord by inserting an expandable polymer underneath the lamina. Then observe the histological change and NSP protein level at compressed spinal cord section, as well as neuronal apoptosis.Result Ischemia of sectional spinal cord was getting serious progressively. Proliferation of microglia and activation of tPA were found in injured area, starting from 24h after implantation of the polymer, and disappeared at 6w. Protein lever of NSP increased from 24h and reach the top at 48h. But it dropped to its normal value at 1w and even lower at 6w. From 2w after surgery, we can see apoptotic neurons in the spinal cord section and massive apoptosis at 6w.Conclusion By establishing the model of chronic ischemic impairment, we found that NSP increased significantly in injured area in early phase of sustained compression of spinal cord, triggered by proliferation of microglia and activation of tPA. The upregulation of NSP level may be an innate protecting mechanism because neuronal apoptosis appeared only when NSP level dropped to normal value or lower.