大剂量甲基强的松龙对大鼠急性脊髓损伤后c-fos及HSP 70表达的影响

目的:探讨大剂量甲基强的松龙(MP)对大鼠急性脊髓损伤(ASCI)后c-fos及热休克蛋白70(HSP70)表达的影响。方法:选用48只大鼠建立ASCI模型,应用免疫组化方法和图像分析技术研究MP组和NS组在伤后1,3,6h和1,2,3d脊髓组织中c-fos、HSP70的表达。结果:MP组与NS组脊髓损伤组织中存在c-fos、HSP70的阳性表达。ASCI后c-fos表达增加,3h最为显著,MP组在伤后1,3,6hc-fos的表达明显低于NS组(P<0.05);ASCI后HSP70表达增加,1d最为显著,MP组在伤后6h(P<0.05)、1d(P<0.01)、2d(P<0.01)HSP70的表达明显高于NS组。结论:MP可以抑制c-fos和促进HSP70的表达,对ASCI的治疗有效。

Effect of high-dose methylprednisolone on expressions of c-fos and heat shock protein 70 after acute spinal cord injury in rats

Objective:To discuss the effect of high-dose methylprednisolone (MP) on the expressions of c-fos and heat shock protein 70 (HSP70) after acute spinal cord injury (ASCI) in rats. Methods:The rat model of ASCI was established by using Allen's method in 48 female Wistar rats,and the rats were treated with MP (MP group) or normal saline (NS group) after ASCI. The expressions of c-fos and HSP70 were determined by immunohistochemical method and image analytical technology 1,3,and 6 hours and 1,2,and 3 days after ASCI,respectively. Results:The expressions of c-fos and HSP70 in spinal cord tissues were positive in both NS group and MP group. The expression of c-fos increased after ASCI,and reached the peak 3 hours after ASCI. The expression of c-fos in MP group was significantly lower than that in NS group 1,3,and 6 hours after ASCI (all P < 0.05). The expression of HSP70 increased after ASCI and reached the peak 1 day after ASCI. The expression of HSP70 in MP group was significantly higher than that in NS group 6 hours,1 day,and 2 days after ASCI (P < 0.05,P < 0.01,and P < 0.01,respectively). Conclusion:MP could inhibit the expression of c-fos and stimulate the expression of HSP70,and thus it is effective in treating ASCI.