Neuritin在大鼠脑外伤合并骨折过程中的作用研究

目的：研究脑外伤合并股骨骨折的骨痂中Neuritin的表达及血清中变化，探讨中枢神经系统损伤加速对骨折愈合的作用，为临床难治性骨创伤提供新的理论依据。方法：取96只雄性SD大鼠随机分成：A组正常组8只、B组单纯骨折组40只、C组单纯脑外伤组8只及D组骨折合并脑外伤组40只，做股骨骨折和采用脑损伤液压装置建脑损伤模型，术后3、7、14、21、28天取血离心，ELISA法测血清中的Neuritin值。分时间处死B组和D组，取骨痂做切片，行免疫组织化学染色，观测各时间点骨痂中Neuritin的变化和骨折愈合情况。结果：①免疫组织化学染色：骨折愈合过程中血管内皮细胞、软骨细胞及成骨细胞的胞浆中有阳性表达，并显色强。D组1w至3w时的Neuritin阳性细胞百分数均高于B组有显著性统计意义（P〈0．05），但4周时（P〉0．05）。②血清浓度值：A组值（81．37±1．37），B组、C组、D组3天（94．94±3．77107．28±3．46118．35±1．43）逐渐升高，2周达到高峰（110．18±1．48131．89±3．26161．48±1．46），然后下降，3d至3w时各组有显著性统计意义（P〈0．05），4周下降为略高于正常（P〉0．05）。结论：血清和骨痂中Neuritin的表达显著升高，提示Neuritin可能是大鼠股骨骨折合并脑损伤时促进骨折修复的重要因素一。

Expression of Neuritin in Brain Trauma with Femur Fracture in Rats

Objective： To analyze the changes in the expression levels of serum Neuritin and Neuritin in callus of femoral fracture after brain injury in SD-rats, and to investigate the relationship and mechanism of central nervous system injury on fracture healing, in order to provide new theoretical foundation for the treatment of refractoriness fracture for clinical selectivity. Methods： A total of ninety-six SD-rats were selected and were randomly divided into four groups ： group A,negative control（n=8）;group B, brain injury group （n=8） ; group C,only femoral fractures in 40 rats; （n=40）, and group D, fracture with cerebral trauma group （n=40）. rat model of fracture and using modified hydraulic equipment, the rat model of cerebral trauma was established by surgery. Blood of the rats were taken at day 3, 7, 14,21 and28 get the serums. Serum Neuritin were detected by ELISA method.Group B and D were randomly selected and osteotylus samples were obtained. Tissues were stained by immunohistochemistry to observe the expressions of Neuritin in callus and the fracture healing. Results： （1）The immunohistochemical staining indicated that the positive expression of Neuritin was strong in the cytoplasms of the fibroblasts,the mesenchymal cells,the vascular endothelial cells and the osteoblasts, with a higher color intensity. The number of the positive cells was greater in Group D than in Group B.（2） serum Neuritin：Neuritin serum density value in A group （81.37± 1.37）,B group,C group and D group increased to （94.94± 3.77 107.28± 3.46 118.35± 1.43）at 3d after surgery, reached its maximum in two week （110.18± 1.48 131.89± 3.26 161.48± 1.46）,and then began to decline, and declined to normal in the 4th weeks. There was statistical significance in the expression of the lever of Neuritin in serum is higher in fracture with brain injury group than other groups from3d to 3w. Conclusion： The up regulation of Neuritin in callus and serums may be able to accelerate the process of fracture healing after brain injury.