去势延迟雄性小鼠骨折愈合

Castration retards fracture healing in male mice

目的观察去势雄性小鼠骨折愈合的情况,探讨男性骨质疏松骨折愈合过程。方法 40只7周龄C57BL/6J雄性小鼠,其中8只作为基线组,32只随机分为对照组与去势组,小鼠去势后1周建立右股骨中段骨折模型。术后2周和4周,测量血清睾酮浓度,骨折端骨密度(BMD)。骨折愈合情况通过显微CT和组织学切片显示。结果去势后小鼠血清睾酮浓度明显下降;术后4周,与对照组相比,去势组BMD明显降低。三维重建图像显示去势组骨痂改建差于对照组。病理切片可见去势组初级骨小梁少于对照组,骨痂重建差于对照组。结论去势延迟的骨折的愈合,表现在骨折区骨量减少以及骨改建延迟,本研究为男性骨质疏松骨折的研究提供了动物模型。

Objective To observe the process of fracture healing in castrated male mice, and to investigate the process of osteoporotic fractures in men. Methods Forty 7-week C57BL/6J male mice were enrolled in this study. Among them, 8 mice were divided into baseline group, and the remaining 32 mice were randomly divided into control group and castration group. One week after castration, mouse model with the fracture of the right middle femur was established. At the 2~a and the 4~h week after the operation, serum testosterone was detected. Bone mineral density （BMD） and bone mineral content （BMC） of the callus were also detected. The conditions of fracture healing were observed by micro-CT and histological sections. Results In castrated mice, serum testosterone decreased significantly. At the 4~h week after the operation, BMD and BMC in castration group decreased significantly comparing to that in control group. The three-dimensional reconstruction image showed that the callus in castration group was worse than that in control group. The results of HE staining sections showed that the primary bone trabeculae in castration group were less than that in control group, and the reconstruction of callus in castration group was worse than that in control group. Conclusion The retarded fracture healing process caused by castration in male mice shows decreased bone mass and delayed bone remodeling in the callus area. This study provides an animal model for the study of male osteoporotic fractures.