雌激素对去卵巢大鼠松质骨中骨保护素mRNA表达的影响  

Effect of Estrogen on OPG mRNA Expression in Cancellous Bone of Ovariectomized Rats

作　　者：杨召[1] 杨华[1] 姚振强[1] 李宏钧[2] 

机构地区：[1]云南省第一人民医院骨科,昆明市金碧路172号650032 [2]中国医学科学院昆明医学生物研究所分子实验室,昆明650118

出　　处：《中国矫形外科杂志》2003年第6期399-401,共3页Orthopedic Journal of China

基　　金：国家自然科学基金资助项目 NO :49860 0 74

摘　　要：目的 :通过去卵巢大鼠予雌激素后 ,腰椎内OPGmRNA的表达进一步探讨雌激素防治骨质疏松的分子机制。方法 :雌性 3月龄SD大鼠 3 6只 ,随机均分为卵巢切除 +雌激素 (倍美力 )预防组 (EP) ,骨质疏松组 (卵巢切除OVX)及正常对照组 (SHAM ) 3组。术后 12周处死大鼠 ,取第 3腰椎椎体 ,异硫氰酸胍一步法提取总RNA ,嵌套式反转录聚合酶链反应 (NRT PCR)扩增待检测各组OPGmRNA的表达。同时取第 4腰椎椎体 ,行骨组织形态计量学检测。结果 12例腰椎骨组织中 ,EP组 10例OPGmRNA呈阳性表达 (阳性率 83 .3 % ) ,OVX组 2例呈阳性表达 (阳性率 16.7% ) ,而SHAM组 12例均呈阳性表达。统计学处理 :EP组与OVX组有高度显著性差异 (P <0 .0 1) ,EP组与SHAM组无显著性差异 (P >0 .0 5 )。骨组织形态计量学检测 ,OVX组骨体积、骨小梁数目均比SHAM组显著减少 ,而骨小梁间隔显著增大。与OVX组比较 ,EP组骨体积、骨小梁厚度增加 ,骨小梁间隔稍有减小 ,无统计学意义。EP对骨小梁数目无明显影响。结论 :雌激素通过增强松质骨中OPGmRNA的表达 ,抑制破骨细胞性骨吸收 ,从而对去卵巢大鼠的骨质疏松有明显的预防作用。Objective: To investigate the molecular mechanism of estrogen to prevent osteoporosis in ovariectomized (OVX) rats through examining osteoprotegerin (OPG) mRNA expression in lumbar vertebra.Methods:Thirty-six female Spague-Dauley rats aged 3 months were divided into three groups:OVX + Estrogen-Premarin(EP),OVX+Saline(OVX)and Sham-OVX Control (SHAM) with 12 rats in each group.All rats were sacrificed at 12 weeks after surgery and specimens of the third lumbar vertebrae were procured for total RNA extraction using single-step method by acid guanidinium thiocyanate-phenol-chloroform.Nested reverse transcriptase polymerase chain reaction (NRT-PCR) was applied to amplify OPG mRNA and its gene expression was examined in each group.Meanwhile,the fourth lumbar vertebrae were processed for histomorphometric analysis.Results:Of 12 lumbar vertebrae,10 in EP(83.3%) showed positive OPG mRNA expression,while only 2 in OVX(16.7%) expressed OPG mRNA positively.All the specimen in SHAM showed positive OPG mRNA expression.X 2 test revealed that there was highly significant difference existing between EP and OVX( P<0.01 ).However,no significant difference was found between EP and SHAM ( P>0.05 ).Parameters of bone histomorphometric analysis showed that BV/TV,Tb.Th.and TN in OVX were evidently lower but Tb.Sp.greater than in SHAM.In comparison with OVX,EP significantly increased BV/TV and Tb.Th.Although EP also decreased Th.Sp.,no statistic difference was found between EP and OVX.EP did not produce distinct effect on TN.Conclusion:Estrogen can effectively prevent osteoporosis in ovariectomized rats by up-regulating OPG mRNA expression and inhibiting osteoclastic bone resorption in concellous bone.

关 键 词：雌激素 去卵巢大鼠 松质骨 骨保护素 MRNA 骨质疏松 

分 类 号：R58[医药卫生—内分泌]