DXA检测糖尿病性骨质疏松大鼠骨密度的部位选择

Optimal site for DXA to detect bone mineral density in diabetic osteoporosis rats

目的:通过观察糖尿病性骨质疏松大鼠模型骨密度(BMD)下降部位随时间的变化规律,探讨双能X线BMD仪(DXA)检测糖尿病性骨质疏松大鼠BMD的最佳部位。方法:选取无特定病原体级雌性3月龄SD大鼠30只,采用数字表法随机分成对照组和Ⅰ型糖尿病(T1DM)组,每组15只。对照组不做任何处理,T1DM组一次性腹腔注射链脲佐菌素50mg/kg,制作T1DM大鼠模型。应用DXA每月测定一次全身及局部感兴趣区BMD。3月末处死大鼠,测定离体腰椎、股骨等感兴趣区的BMD。结果:与对照组相比,T1DM组大鼠各腰椎和股骨各段的BMD随时间变化均有明显下降;与离体BMD相比,T1DM组大鼠腰椎L2-L5和股骨远心端的BMD最稳定,而腰椎L1、L6在体BMD和离体BMD相差较大。结论:腰椎的L2-L5和股骨远心端为DXA测量T1DM骨质疏松大鼠BMD的最佳部位。

Objective To observe the time-dependent changes of bone mineral density（BMD） in different parts of rats with diabetic osteoporosis, and to explore the best site for dual-energy X-ray absorptiometry（DXA） measurement of BMD in rats with diabetic osteoporosis. Methods Thirty female Sprague-Dawley rats aged 3 months without specific pathogens were randomly divided into control group and type Ⅰ diabetes mellitus（T1DM） group, with 15 rats in each group. The rats in control group received no treatment, while those in T1DM group was injected intraperitoneally with 50 mg/kg streptozotocin once to establish T1DM rat models. DXA was used to measure the BMD of the whole body and regions of interest once a month. Three months later, the rats were killed and the BMD of the lumbar, femur and other regions was measured in vitro. Results Compared with the control group, the T1DM group showed that the BMD in each segment of the lumbar and the femur was significantly decreased with time. Compared with in vitro BMD, the BMD of lumbar L2-L5 and distal femur in T1DM rats was the most stable, while the in vivo BMD and in vitro BMD of lumbar L1 and L6 showed significant differences. Conclusion Lumbar L2-L5 and distal femur were the optimal sites for DXA to detect BMD in rats with T1DM osteoporosis.