雷奈酸锶防治大鼠失用性骨质疏松的研究

The effects of strontium ranelate in preventing disuse-induced osteoporosis in rat

目的通过干预拟失重大鼠骨质疏松动物模型,探讨雷奈酸锶对拟失重大鼠骨量、骨代谢和生物力学性能的影响。方法 3月龄SD大鼠24只,随机均分为对照组(A)、骨质疏松组(B)、雷奈酸锶组(C),每组8只。B、C两组大鼠采用尾悬吊法制备失用性骨质疏松大鼠模型,C组给予雷奈酸锶干预(1g/kg/d)。4周后处死所有大鼠,留取尿液、血清检测血P1NP值、尿DPYD/Cr、NTX/Cr值,右侧胫骨制备非脱钙组织切片并行骨形态计量学检测,右侧股骨检测骨密度,取左侧股骨行三点弯曲试验,检测其最大载荷。结果 B组血P1NP值显著低于A、C组,尿DPYD/Cr、尿NTX/Cr值显著高于A、C组,C组显著高于A组(均P<0.05);B组骨小梁体积、骨小梁数量、骨小梁厚度、骨形成率显著低于A、C组,B组破骨细胞数、骨吸收长度比显著高于A、C组;股骨骨密度由高到低依次为A、C、B组,组间差异均有显著性(P<0.05);最大载荷B组显著低于A组(P<0.05)。结论雷奈酸锶可部分阻止尾悬吊导致的大鼠骨质量和力学性能的下降。

Objective To understand the effects of strontium ranelate on bone mass,bone matablism and biomechanical properties of osteoporotic rats induced by disuse. Methods 24 3-month old SD rats were randomized into 3 groups of 8 animals each： Normal control group（ A）,osteoporosis group（ B）,and strontium ranelate treatment group（ C）. Rats in group B and C were subjected to tail suspension,and rats in group C were administered with strontium ranelate（ 1g / kg / d）. All rats were sacrificed 4 weeks later. Content of P1NP in blood serum and DPYD / Cr,NTX / Cr in urine were detected. The right tibias were prepared for undecalcified sections and thereby bone histomorphometry analysis,and right femurs were collected for bone mineral density assessment,three-point bending test was performed on left femurs to assess the maximum load.Results 1. P1NP concentration in group B was significantly lower than that of group A and C. Tail suspension markedly increased the levels of DPYD / Cr and NTX / Cr. Strontium ranelate could retard the increase but still significantly higher than those of normal rats（ P 0. 05）; 2. Trabecular volume,number,thickness,and bone formation rate in group B were significantly lower than those in group A and C,while the osteoclast number and erosion percentage were markedly higher in group B,as compared to those of group A and C（ P 0. 05）; 3. Bone mineral density in group A,C and B showed a subsequently decreasing manner,with significant difference between any two groups（ P 0. 05）; 4. The results of biomechanical test showed markedly lower maximum load in group B as compared to group A（ P 0. 05）. Conclusion Strontium ranelate could partially prevent the deterioration of bone quality and biomechanical property in disuse-induced osteoporosis rat.