碱性成纤维细胞生长因子对大鼠牵张性脊髓损伤后c-fos基因表达的影响

目的观察碱性成纤维细胞生长因子(basicfibroblast growthfactor,bFGF)对牵张性脊髓损伤后c-fos基因表达的影响.方法用特制的脊柱撑开器放置在大鼠脊髓T12～L3椎体横突上纵向牵张,同时皮层体感诱发电位监测,建立大鼠牵张性脊髓损伤模型.用免疫组织化学染色法观察c-fos基因的表达,并用计算机图像分析系统进行定量分析.结果脊髓损伤后神经元C-FOS蛋白D值较正常组显著增加,表达高峰出现在损伤后2 h,而bFGF治疗组在各时相点均低于对照组(P＜0.05,P＜0.01).结论碱性成纤维细胞生长因子能显著抑制脊髓损伤后c-fos基因的表达,这可能是bFGF保护神经元并减轻脊髓损伤的机制之一.

Inhibition effects of basic fibroblast growth factor on c-fos gene expression after tractive spinal cord injury in rats

Objective To observe the effects of basic fibroblast growth factor on c-fos gene expression in spinal cord neurons of rats after tractive spinal cord injury. Methods The animal model of SD rats with tractive spinal cord injury was established through tracting T_ 13-L_2 spine longitudinally with a special spinal tractor that was put on parapophysis of T_ 12-L_3 vertebrae after exposing T_ 13-L_2 spinal cord via dual laminectomy, meanwhile spinal cord function was monitored by cortical somatosensory evoked potential (CSEP). Forty model rats were randomly divided into 2 groups, the bFGF treatment group (n=20) with bFGF injection into the subarachnoid cavity and the control group (n=20) with saline injection. Five SD rats without any treatment served as normal control. The c-fos gene expression was detected with immunohistochemistry and analyzed quantitatively with image system of computer. Results The c-fos gene expression in tractive spinal cord injury was higher than that in normal control group, especially increased markedly in damaged neurons. The peak value of c-fos gene appeared in 2 h after the injury, but c-fos level in the bFGF treatment group was lower evidently than that in the control group at the different sacrificed time (P<0.05 or P<0.01). Conclusion Basic fibroblast growth factor can inhibit significantly the c-fos gene expression in spinal cord after tractive injury, which may be one of the mechanism that bFGF protect neurons and relieve lesion in spinal cord.