上皮钙离子通道TRPV6在脑外伤合并骨折大鼠模型骨折部位表达的实验研究

A experimental study on the expression of TRPV6 in the fracture site of rats with fracture combined brain injury

目的研究大鼠股骨干骨折合并脑外伤时骨折部位瞬时性受体电位香草精受体6(TRPV6)的表达情况,探讨其与脑外伤促进骨折愈合的相关性。方法 12周雄性SD大鼠80只,随机分为5组,每组16只。A1组为骨折合并脑外伤1周组,A2组为骨折合并脑外伤2周组,B1组为单纯骨折1周组,B2组为单纯骨折2周组,C组为正常对照组。A组制作脑外伤合并股骨干骨折模型,B组制作单纯股骨干骨折模型。摄X线片后截取骨痂,HE染色及Masson染色观察骨痂生长情况及组织形态,免疫组化染色及RT-PCR检测TRPV6的表达。结果标本的HE染色及Masson染色可见骨折合并脑外伤组骨痂形成及成熟度快于单纯骨折组(P<0.05);免疫组化结果可见骨痂中TRPV6呈阳性反应,A2组TRPV6阳性表达的光密度平均值高B2组(P<0.05)。RT-PCR显示A、B组均有TRPV6 mRNA表达,A2组表达显著高于B2组(P<0.05)。结论脑外伤对骨折愈合有促进作用,其机制可能与脑外伤后骨折部位TRPV6表达水平升高相关。

Objective To investigate the expression levels of transient receptor potential cation channel subfamily V member 6（TRPV6） in the fracture site of rats with femoral fracture,brain injury and explore the effect of the brain injury on the fracture healing. Methods 80 SD rats（ age：12 weeks）were randomly divided into 5 groups,8 rats in each group. The rats in group A1 and group A2 had femoral fracture and brain injury for 1,2 weeks respectively,and the rats in group B1,B2 had fracture without brain injury for 1,2 weeks respectively. The group C was normal control group. The rats of each group were taken the X-ray films one or two weeks after operation respectively at first,then the bone callus were intercepted to observe the histological changes by HE staining and Masson staining,and to measure the expression levels of TRPV6 by immunohistochemical staining and RT-PCR. Results The HE staining and Masson staining of group A shows the bone callus was growing earlier and greater than that in group B at the same time point. The immunohistochemical staining indicated that the TRPV6 was positively expressed in bone callus,the average IOD in group A2 was more than group B2（ P 〈0. 05）. The result of RT-PCR demonstrated the expression of TRPV6 in group B2（ P 〈0. 05）. Conclusion Brain injury can promote the fracture healing process,which is probably related to the higher expression levels of TRPV6 in the fracture site.