DXA测量活体大鼠骨的精密性及骨丢失的检测  

Dual-energy X-ray absorptiometry of rats:precision and measurement of bone loss in vivo

作　　者：陆泽元[1] 廖二元[1] 伍贤平[1] 伍汉文[1] 周智广[1] 邓小戈[1] 

机构地区：[1]湖南医科大学第二附属医院代谢内分泌研究所

出　　处：《中国骨质疏松杂志》2001年第3期199-201,2229,共4页Chinese Journal of Osteoporosis

摘　　要：目的　了解QDR - 45 0 0A型双能X射线吸收法 (DXA)测量活体大鼠的精密性和探测去卵巢后大鼠骨丢失的能力。方法　测量 15只体重为 2 0 2～ 311g的SD大鼠全身、股骨及腰椎的骨密度 (BMD) ,每只大鼠测量 3次 ,可得变异系数 (CV) ,15只大鼠CV的平均值为该指标的批内CV。结果　①全身、股骨、腰椎BMD的批内CV分别为 0 71%、2 0 2 %和 2 44 % ,全身BMD的批内CV显著低于股骨和腰椎 (P <0 0 5 ) ;②全身BMD的批间CV为 0 99% ,股骨整体为 2 81% ,腰椎总体 (L3～L6 )为 3 42 % ;③术后 4周去卵巢组全身、股骨、腰椎BMD与假手术组比较无显著性变化 ,而股骨远侧干骺端BMD低于假手术组 (P <0 0 5 ) ;④去卵巢后 14周腰椎总体 (L4～L6 )的BMD低于假手术组(P <0 0 5 )。结论　QDR - 45 0 0A型DXA测量大鼠全身、股骨和腰椎BMD有较好的精密性 ,全身优于局部骨骼 ;Objective\ To investigate the precision of dual energy X ray absorptiometry (DXA) in rats in vivo and assess the ability of the technique to detect bone loss in ovariectomized rats. Methods\ Bone mineral density(BMD) of whole body,lumbar spine and femur of 15 SD rats(mean weight 253±32g)were studied by DXA(QDR-4500A).The reproducibility was determined by making three measurements on each anesthetized rat. Results\ ①The coefficients of variation(CV)of BMD for whole body,at femur and at lumbar spine were 0 71%,2 02% and 2 44%,respectively.The CV of BMD for whole body was significantly lower than that at femur and at lumbar spine( P <0.05).②The long term precision of measurement in rat cadavers over a 20 day period was 0.99% for whole body BMD,2.81% for femur,and 3.42% for lumbar spine(L 3～L 6).③There were no significant differences for the BMD of whole body,femur and lumbar spine at 4 weeks post surgery between OVX rats and sham controls,but the BMD of distal femoral metaphysis was significantly lower in ovariectomized rats than that in sham operated controls ( P <0 05).④The BMD of the lumbar spines(L 4～L 6)in rats was significantly lower at 14 weeks post operation than that in sham controls( P <0 05). Conclusion ①The BMD of whole body,femur and lumbar spine can all be obtained with excellent prcision using QDR-4500A DXA.The precision of whole body BMD was superior to that of local BMD.②The DXA technique has the precision necessary to detect non invasively the bone loss post ovariectomy.

关 键 词：双能X射线吸收法 骨丢失 去卵巢大鼠 骨密度 

分 类 号：Q814.4[生物学—生物工程] R681.1[医药卫生—骨科学]