不同手术时间对骨折愈合过程中VEGF表达的影响

Time interval of operation on VEGF expression in bone during fracture healing

目的观察不同手术时间对实验大鼠骨折愈合过程中血管内皮细胞生长因子（VEGF）表达的影响.方法对192只大鼠股骨进行闭合骨折造模,在造模后第1、3、5、7、11、14天分别对骨折采取切开复位内固定手术,并在骨折后第1、3、5、7、11、14、21、35、49天对大鼠骨折端进行VEGF免疫组化染色观察,对其表达结果进行统计分析.结果手术操作干预了实验大鼠骨折愈合不同阶段VEGF的表达强度及表达时间.第7、11天手术组能较好地促进骨折端VEGF表达,且能持续更长时间,第14天手术组次之.第5天手术组仅在表达强度上高于未手术组,当天手术组与未手术组则无明显差别.而第3天手术组在骨折愈合的各阶段均处于较低水平,且低于未手术组.结论手术操作时机能影响实验大鼠骨折端VEGF的表达,可能导致二次损伤加速现象,但最佳手术时机在第1~2周时段,骨折后几天内即进行手术操作可能不利于骨折的愈合.

Objective To observe the effect of time interval of operation on the expression of vascular endothelial growth factor （VEGF） in bone during fracture healing in rats. Methods Closed femoral fracture was induced in 192 Wistar rats. The frac-ture was treated with open reduction and internal fixation operation at 1, 3, 5, 7, 11 and 14d after fracture. The expression of VEGF in fracture end at different time points （d1, 3, 5, 7, 11, 14, 21, 35 and 49） were detected with immunohistochemical staining. Re-sults The expression of VEGF was strongest and last longer in rats operated at d7 or d11 after fracture, fol owed by those oper-ated at d14. The expression intensity was higher in rats operated d5 after fracture than those without operation. There was no dif-ference in VEGF expression between rats operated at d1 and non-operated rats;while rats operated at d3 presented low VEGF expression at al time points of fracture healing,which even lower than that in rats without operation. Conclusion The results sug-gest that the optimal timing of surgery may be within the 1~2 weeks after fracture.