外源性甲状旁腺素对小鼠骨折愈合的影响  

Effects of exogenous PTH1-34 on healing of bone fracture in mice

作　　者：谢杨丽[1] 苏楠[1] 金旻[1] 赵玲[1] 陈林[1] 

机构地区：[1]三军医大学大坪医院野战外科研究所创伤实验室,创伤、烧伤与复合伤国家重点实验室,重庆400042

出　　处：《第三军医大学学报》2010年第10期1003-1007,共5页Journal of Third Military Medical University

基　　金：国家重点基础研究发展计划(973计划,2005CB522604);国家自然科学基金重点项目(30530410)~~

摘　　要：目的观察外源性甲状旁腺素(parathyroid hormone,PTH)对骨折愈合的影响。方法按闭合性骨折制作模型的方法建立小鼠胫骨骨折模型,并在观察期内每天皮下注射PTH1-34(80μg/kg),取材,检测血清钙磷水平,X线摄片与组织学观察骨折愈合情况,检测第1、3、7、14、21天和第28天骨痂组织中调节骨代谢的相关基因mRNA的表达情况。结果PTH1-34不影响血清钙磷水平,但能在一定程度上使骨折后7d软骨痂增加,骨折后14d残余软骨痂减少,骨折后21d骨髓腔中残余编织骨减少。在骨折的早期(3～7d),PTH给药组中的增殖相关基因PCNA和IGF-1mRNA的表达与对照组相比明显增高(P<0.05);在骨折的中晚期(7～28d),PTH给药组中的成骨相关基因Cbfa-1、Col-1、OCN、ALPmRNA的表达与对照组相比,有明显增高(P<0.01),在此时期,RANKL/OPGmRNA的比值也有统计学差异(P<0.01)。结论在骨折愈合过程的不同阶段,外源性PTH可以通过调节不同的骨代谢相关基因的表达来促进骨折的愈合。Objective To investigate whether exogenous parathyroid hormone （PTH） can stimulate bone fracture healing.Methods Closed proximal tibia fracture was created and stabilized with an intramedullary pin in 60 2-month-old mice.The 50 surviving mice were randomly and equally divided into PTH treatment group and control group.Mice of different groups received a daily injection of PTH1-34 （80 μg/kg） or saline for 1 to 28 d post-fracture,and the concentration of serum calcium and phosphorus were measured and callus tissue properties was analyzed at 1,2 and 3 weeks post-fracture by radiography and histology.Total RNA was extracted from callus tissues,and the expression levels of bone formation-related genes were evaluated by real-time PCR.Results The serum calcium and phosphorus levels were not significant different between 2 groups.In 7 d post-fracture,cartilaginous callus areas were increased in PTH-treated mice compared with that of control mice.In contrast,in 14 d post-fracture,the remnant cartilaginous callus areas were smaller in PTH-treated mice than that in control mice.The remnant fibrous bone areas in marrow cavity were also reduced in PTH-treated mice compared to control mice in 21 d after fracture.In the early stages of fracture （3 to 7 d）,compared with the control group,the PCNA and IGF-1 mRNA expressions were obviously increased in PTH treatment group.In the middle and late （7 to 28 d） stages of fracture,compared with the control group,the Cbfa-1,Col-1,OCN,ALP mRNA expressions were significant increased in PTH treatment group.Conclusion These results indicate that exogenous PTH enhances bone fracture healing in terms of increasing callus areas,endochondral bone formation and osteoblastic bone formation,possibly through upregulating PCNA,IGF-1,Cbfa-1,Col-1,OCN,and ALP at different stage of the healing process.

关 键 词：甲状旁腺素 骨折愈合 骨代谢 

分 类 号：R683.42[医药卫生—骨科学] R364.3[医药卫生—外科学]