摘要
目的观察碱性成纤维细胞生长因子(bFGF)对牵张性脊髓损伤后细胞凋亡及相关基因表达的影响,探讨bFGF对脊髓损伤保护作用的分子机制。方法大鼠脊髓T13～L2经牵张损伤,皮层体感诱发电位(CSEP)监测P1～N1波幅下降至术前波幅70%后,于损伤平面以下经蛛网膜下腔置细导管,治疗组分别于术后即刻1、2、3、4、8、12及24h经细导管注入bFGF溶液20μl(含bFGF20μg),对照组在相同时间注入等量生理盐水,然后于术后6h、1、4、7、14及21d处死取材,采用原位末端标记法(TUNEL)及免疫组织化学观察脊髓细胞凋亡及p53、bax、bcl2表达的变化情况,应用电生理观察大鼠的神经功能情况,并进行对比分析。结果术后4、7、14、21d,治疗组TUNEL法染色阳性细胞数明显低于对照组(P<0.01)。术后4、7、14、21d,治疗组p53、bax的阳性细胞数明显低于对照组,治疗组各时相点bcl2的阳性细胞数明显高于对照组,治疗组大鼠的神经功能恢复与对照组相比差异有统计学意义(P<0.01)。结论bFGF能通过抑制p53、bax蛋白的表达及促进bcl2蛋白表达来抑制牵张性脊髓损伤后细胞凋亡,从而保护损伤的脊髓组织,这可能是bFGF对脊髓损伤具有的保护作用机制之一。
Objective To observe the effect of basic fibroblast growth factor (bFGF) on cell apoptosis and the expression of correlative genes and to study the molecular mechanism of the protective effects of bFGF against spinal cord injury.Methods After tractive spinal cord injujry of T13-L2 and P1-N1 wave was decreased to 70% of the baseline mornitored by cortical smatosensory evoked potential,a thin plastic tube was situated in subarachnoid space below the injured level.In the treatment group,20 μl (20 μg) bFGF solution was infused via the thin tube at once,1,2,3,4,8,12 and 24 h after injury respectively.The saline-treated rats were subjected to the infusion of the equal volume of normal saline at the same time points.The rats were killed on the 6 h,1,4,7,14,21 day postoperatively (n=4 in each time point).The cell apoptosis and the expression of p53,bax and bcl-2 genes were detected.The functional recovery of spinal cord was examined by electrophysiological technique.Results Four,7,14 and 21 days after injury,the number of the TUNEL staining positve cells in the treatment group was less than in control group (P< 0.01).Immunohistochemical staining revealed that the expression of p53 and bax proteins was lower,and bcl-2 was higher in the treatment group than in control group in 4,7,14,21 days after injury (P< 0.01).Neuroalogical function recovery had a significant difference between the treatment group and control group (P< 0.01).Conclusion bFGF can inhibit the cell apoptosis through inhibiting the expression of bax and p53 proteins and promoting the expression of bcl-2 protein so as to protect injured spinal cord,which may be one of the protective mechanisms of bFGF against spinal cord injury.
出处
《中华实验外科杂志》
CAS
CSCD
北大核心
2005年第6期724-726,共3页
Chinese Journal of Experimental Surgery
