中等强度运动对去卵巢大鼠骨量及cGMP-PKG Ⅱ-EnaC通路的影响  

Effects of moderate intensity training on bone mass and cGMP-PKGⅡ-EnaC in rats with ovariectomy

作　　者：郑陆[1] 陈晓红[1] 王智强[1] 王文荣[1] 刘洋[1] 

机构地区：[1]首都体育学院,北京100191

出　　处：《中国康复医学杂志》2016年第6期617-624,共8页Chinese Journal of Rehabilitation Medicine

基　　金：北京市教委科研基地科技创新平台项目(PXM2012-014206-000037)

摘　　要：目的:通过中等强度跑台运动干预,探讨运动经cGMP-PKGⅡ-ENaC通路对去卵巢大鼠骨量的影响效应,为阐明有氧运动对骨量的影响及机制提供实验依据。方法:3月龄雌性SD大鼠随机分为10组:BC(基础对照组)、SHAM4、8、12(假手术4、8、12周)组;OVX4、8、12(去卵巢对照4、8、12周)组;OVX+T4、8、12(去卵巢+运动4、8、12周)组。运动组采用跑台训练,坡度5°,5d/w。以DXA测定大鼠全身骨密度(bone mineral density,BMD);以ELISA测定血清环鸟苷酸(cyclic guanosine monophosphate,cGMP)含量;以Western blot和实时PCR法分别测定cGMP依赖性蛋白激酶GⅡ(cGMP dependent protein kinase,PKGⅡ)和ENa C-γ的蛋白及mRNA表达量。结果:运动组大鼠BMD呈现出随运动时间增长而增加态势,OVX+T 12组BMD显著高于同期OVX组(P<0.01),OVX+T 8和12虽仍低于同期SHAM组,但无显著性差异。与同期OVX组比较,OVX+T8、12组cGMP血清水平、股骨PKGⅡmRNA、ENaC-γ mRNA表达均显著增加(P<0.05),但仍均低于同期SHAM组。与同期OVX组比较,OVX+T4、12组PKGⅡ蛋白表达显著增加(P<0.05),但仍低于同期SHAM组(P均<0.01),运动组PKGⅡ蛋白降低程度显著减缓。OVX+T4、8、12组ENaC-γ蛋白表达均显著高于同期OVX组(P均<0.01),但仍低于同期SHAM组(P<0.05—0.01),降低程度显著减缓。结论:中等强度跑台运动干预能增加去卵巢大鼠cGMP浓度,同时上调骨PKGⅡ、ENa C-γ蛋白及mRNA的表达;中等强度跑台运动能够有效地增加去卵巢大鼠骨密度;运动增加去卵巢大鼠骨量的机制与c GMP-PKGⅡ-ENaC通路激活密切相关。Objective： To determine the effects of moderate intensity treadmill running on bone mass by cGMP-PKGⅡ- EnaC in ovariectomy（OVX） rats, and provide experimental basis for exploring the mechanism of moderate in- tensity aerobic training on bone mass. Method： Three-month-old female SD rats were divided into 10 groups randomly. They were basal control （BC） group, SHAM4, 8, 12 （pseudooperation 4, 8, and 12 weeks）, OVX4,8,12 （Ovariectomy 4, 8, and 12 weeks）, OVX＋T 4, 8, 12 （Ovariectomy＋training 4, 8, and 12 weeks）. OVX＋T groups respectively received 4, 8, and 12 weeks aerobic training on treadmill （5 days/week, slope 5°）. BMD was measured by dual energy X-ray absorptiometry （DXA）. Serum cGMP was determined by ELISA. PKG Ⅱ and ENaC-y mRNA of femur were detected by real-time quantitative PCR （qRT-RCR）. PKG Ⅱ and ENaC-7 level of femur were detected by western-blot. Result： BMD showed growing along with the training time in OVX＋T. BMD in OVX＋T12 showed significant higher than that in OVX12 （P〈0.01）. BMD in OVX＋T8 and OVX＋T12 showed lower than that in SHAM8 and SHAM12 but not significant. Comparing with OVX8 and OVX12, serum cGMP, PKG Ⅱ mRNA, and ENaC-y mRNA were significantly elevated in OVX＋T8 and OVX＋T12 respectively （P〈 0.05）, but lower than that in SHAM8 and SHAM12. Compared separately with OVX4 and OVX12, PKG 11 expression markedly increasing in OVX＋T4 and OVX＋T12 （all P〈0.05）, but lower than that in SHAM4 and SHAM12（all P〈0.01）. Comparing with OVX4 8 and 12, ENaC-7 expression significantly higher in OVX＋T4, OVX＋T8, and OVX＋ T12 （all P〈0.01）, but lower than that in relevant SHAM groups （P〈 0.01--0.05）. Conclusion： The moderate intensity treadmill running intervention increased BMD and increased serum cGMP level, up-regulated PKG Ⅱ mRNA and ENaC-y mRNA expression, PKG Ⅱ and ENaC-y levels in femur of OVX rats. These results may provide a new clue that the mechanism of exercise increasing bone mass in OVX r

关 键 词：中等强度跑台运动 cGMP-PKGⅡ-EnaC通路 骨密度 去卵巢 

分 类 号：R87[医药卫生—运动医学]