The Expression Of GFAP After Cerclage-induced Spinal Cord Injury In BMP-7Rats

[Objective]:To study the changes of expression of GFAP with BMP-7after Manufacturing cerclage spinal cord injury model,and to explore the early treatment of spinal cord injury. The model was to further study the theoretical basis.[Methods]:The preliminary work of our group has established a personalized and repeatable cerclage spinal cord injury model. Fifty-five adult SD (Thirteen-week-old) rats were divided at random into three groups:group A:Blank test group, only the laminectomy and dural sac circumference measurements but don’t cerclage spinal cord. N=15Group B:Controlled trial group.8h decompression after cerclage postoperative. N=20. Group C:Experimental treatment group.2h after intravenous injection given to BMP-7treatment and8h decompression after cerclage postoperative.In the manufacturing cerclage spinal cord injury model process, T13laminectomy to reveal dural, to measure the circumference of the dural sac (Cl) with double-stranded5/0white absorption lines, to measure the length, then to obtain the length C2by the algebraic formula (C2=C1*(?)0.7), the dural sac cross-sectional area was70%of the original area. Each group was executed at24h,1d,3d,7d,14d and21d after surgery. The spinal cord was examinated by HE staining, Immunohistochemistry and terminal dexynucleotidyl transferase(TdT)-mediated dUTP nick end labeling (TUNEL). Neuromotor function test was used BBB score, and inclined plane score. The results were analyzed in each group, and to make correlation. With P<0.05for significant differences.[Results]:Blank group (group A) with neuromotor function BBB scores, inclined plane score, HE staining showed no obvious abnormalities; GFAP-positive cells in rat spinal cord tissue rare expression. The control group compared with the black group, neuromotor function BBB score, inclined plane score lower, the GFAP-positive cells in spinal cord tissue began to increase on the first postoperative day, after the first three days to reach the peak, the difference was statistically significant (data comparison between the groups P<0.05). The Experimental treatment group and the Control group, neuromotor function BBB rating, inclined plane score was significantly higher in the spinal cord GFAP-positive cells increased significantly, GFAP-positive cells peaked in the first three days after surgery, the difference was statistically significant (each group comparison between the data P<0.05).[Conclusion]:1. Comparing the experimental treatment and the control groups, neuromotor function BBB scores, inclined plane scores and GFAP-positive cells were significant differences exist, it can be inferred to increase the expression of GFAP in spinal cord injury after intravenous injection given to BMP-7treatment. This neuroprotective effect may be related to inhibition of neuronal differentiation, promoting proliferation of astrocytes, resulting glial scar in the injury site and suppressing inflammation, thereby reducing the occurrence of secondary damage after spinal cord injur.2.Cerclage induced animal model of spinal cord injury in rats with good repeatability, quantitative and some clinical relevance, the model is an ideal method for modeling of spinal cord injury.3.Higher experssion of GFAP after spinal cord injury is likely to GFAP remaining astrocyte morphology and function stability, it can be inferred to the expression of GFAP in spinal cord injury could protect and repair the damaged nerve cells.