中文摘要：

目的探讨P75神经营养因子受体（P75 neurotrophin receptor,P75NTR）在兔骨折不愈合局部组织中的表达及意义。方法30只新西兰大白兔随机分成A、B、C三组,每组10只。A组建立骨折不愈合模型,B组建立骨折模型,C组不予处理为正常组。骨折不愈合造模成功、骨折模型愈合后,利用免疫组织化学、Western blotting及IPP6.0病理图像分析软件对三组组织中P75NTR的表达进行半定量分析,测定其平均吸光度值及P75NTR与β-action的比值。结果 P75NTR平均吸光度值骨折不愈合组为0.3287±0.0419,骨折组为0.0267±0.0187,正常组为0.0159±0.0136。骨折不愈合组与其他两组比较差异有统计学意义（P〈0.05）,骨折组与正常组比较差异无统计学意义（P〉0.05）;P75NTR/β-action骨折不愈合组为3.6434±0.0596,正常组为0.1390±0.0294,骨折组为0.1489±0.0317。骨折不愈合组与其他两组比较差异有统计学意义（P〈0.05）,骨折组与正常组比较差异无统计学意义（P〉0.05）。骨折不愈合组高表达P75NTR,骨折组和正常组中P75NTR表达较低,骨折不愈合组与其他两组比较差异有统计学意义（两种检测均显示P〈0.05）;骨折组与正常组比较P75NTR的表达无统计学意义（两种检测均显示P〉0.05）。结论 P75NTR在兔骨折不愈合局部组织中表达,且明显高于骨折组和正常组,它可能是骨折不愈合形成的一个重要因素。

英文摘要：

Objective To investigate the expression and significance of P75NTR（P75 neurotrophin receptor） in rabbit nonunion local tissues after fracture. Methods 30 New Zealand rabbits were randomly divided into A,B,and C three groups,with 10 in each group. Group A was the model of nonunion,group B was the model of fracture,and group C was untreated normal group.After nonunion models were established successfully and the fracture models were healed,the expression of P75NTR in the three groups were detected by immunohistochemistry,western blotting and Image-Pro Plus 6. 0 pathological image analysis software,then the average absorbance value and the ratio of P75NTR toβ-action were measured. Results The P75NTR average optical density of the nonunion group,the fracture group and the untreated group were 0. 3287 ± 0. 0419,0. 0267 ± 0. 0187 and 0. 0159 ± 0. 0136,respectively. There were significant differences between the nonunion group and the other two groups（P 〈 0. 05）,while there was no significant difference between the fracture group and the untreated group（P 〉 0. 05）. The ratio of P75NTR to β-action of the nonunion group,the fracture group and the untreated group were 3. 6434 ± 0. 0596,0. 1390 ± 0. 0294 and 0. 1489 ± 0. 0317,respectively. There were significant differences between the nonunion group and the other two groups（P 〈 0. 05）,but there was no significant difference between the fracture group and the untreated group（P 〉 0. 05）. The expression of P75NTR in the nonunion group was significantly higher than that in the other two groups（both P 〈 0. 05）,whereas there was no significant difference between the fracture group and the untreated group（both P 〉 0. 05）. Conclusion P75NTR expressed in rabbit nonunion local tissues and its expression was significantly higher than that in the fracture group and the untreated group. P75NTR may be an important factor in nonunion after fracture.