短时间直接力刺激对后肢去负荷大鼠骨丢失的防护作用

Preventing Effect of Short-time Direct Mechanical Loading Stimulation Against Bone Loss of Hind-Limb Unloaded Rats

目的研究短时力负荷刺激对模拟失重大鼠骨丢失的防护作用。方法采用后肢去负荷大鼠模拟失重,每天给大鼠胫骨施加5 N/10 Hz的横向及纵向力刺激1 min,通过大鼠矿盐含量、生物力学特性及生化指标变化等综合评价力负荷的防护效果。结果短时间直接力刺激可改善机体钙磷平衡,降低股骨干NO含量,增加矿盐含量,改善松质骨的显微结构,增强骨生物力学强度(P<0.05),且胫骨中部横向力刺激效果比径向刺激效果好。结论短时间直接力刺激可有效改善后肢去负荷引起的骨丢失。

Objective To study the effectiveness of mechanical loading stimulation on preventing the bone loss of hind limb unloaded rats.Methods Microgravity was simulated with suspending tail of rat.One minute＇s mechanical loading at 5N/10Hz was performed on the tibia of rat everyday.The bone mineral content,properties of vitodynamics and biochemical markers of bone were tested to evaluate the effectiveness of this countermeasure.Results Short time direct mechanical loading could keep the balance of calcium and phosphate metabolism,decrease the content of nitrogen monoxidum in femur,improve the microstructure of cancellous bone and increase bone mineral content and its intensity.The horizontal mechanical loading of the tibia had the better effect than that of the vertical.Conclusion Short time direct mechanical loading could effectively prevent the bone loss caused by hind limb unloading.