骨折早期调节RANKL表达对骨折愈合影响的实验研究

目的通过对大鼠股骨骨折早期局部应用重组人骨保护素Fc融合蛋白(OPG-Fc),研究调节骨保护素(OPG)和核因子-κB受体活化因子配体(RANKL)的表达变化对骨折早期的影响,探讨其表达调节方式及作用机制。方法 48只雌性SD大鼠随机分成实验组和对照组,每组24只。建立大鼠股骨骨折模型,于术后第7天、第14天、第21天、第28天4个时间节段分批处死模型,标本切片后通过HE染色观察骨折愈合情况,免疫组织化学染色研究破骨细胞数量变化。结果 HE染色示单纯骨折组呈典型骨折愈合过程,而骨折局部注射OPG组骨痂形成及改造提前,骨折愈合加速。免疫组织化学染色显示在第7天、第14天、第21天、第28天各个时间节段单纯骨折组破骨细胞计数值均高于骨折应用OPG组,差异有统计学意义(P0.05)。结论骨折早期调节RANKL表达,当RANKL/OPG比值减小时,骨折局部破骨细胞减少,骨痂形成增多,骨折愈合加速。

Experimental study on the effect of early fracture reluating rankl expression to fracture healing

Objective To investigate the effect of regulating the expression of osteoprotegerin (OPG) and receptoractivator of nuclear factor-KB ligand ( RANKL) on early fracture by local application of OPG-Fc to rats with femoral fracture in the process of early fracture, and so as to explore its expression regulation mode and related mechanism. Methods 48 female SD rats were randomly divided into the experimental group and the control group respectively, and 24 pieces per group. And then open fracture model of rats was established, the animals were sacrificed at 4 time points (7, 14, 21 and 28 day) after operation, after callus specimens were sectioned, the information of fracture healing was observed by HE staining and the change of Osteoclast number was detected by immunohistochemical staining. Results HE staining indicated that the process of fracture healing in the pure fracture group was classical, but the callus formation and reforming in the fracture group of local injections of OPG were ahead of schedule, and fracture healing was accelerated. Immunohistochemical staining showed that the osteocyte count values of the pure fracture group were higher than that of the OPG application fracturegroup at all time points of 7, 14, 21 and 28 day, the difference was statistically significant (P<0.05). Conclusion When regulating RANKL expression in the early stage of fracture, with the decreasing of RANKL/OPG, the number of local osteoclast declines, callus formation increases, and fracture healing is accelerated.