中文摘要：

目的探讨维甲酸（RA）致大鼠骨质疏松模型特点及丹参骨宝的预防作用。方法4mon♀ SD大鼠灌服RA70mg·kg^-1·d^-1造模,然后给予丹参骨宝进行预防,用药时间为28d。用骨组织形态计量学方法测定大鼠第5腰椎松质骨静态、动态参数和观察胫骨中段皮质骨的动态变化情况,大鼠第4腰椎用骨生物力学方法作椎体压缩试验。结果与空白对照组比较,RA组大鼠腰椎生物力学参数下降,腰椎松质骨静态参数（骨组织总面积、骨小梁面积、骨小梁周长）和动态参数均降低,皮质骨骨外膜的骨形成减弱而骨内膜的骨形成增强。与RA组比较,低、中剂量丹参骨宝使腰椎生物力学参数增加。结论RA使大鼠椎骨的几何形状缩小和生物力学性能降低,但骨小梁面积百分数无明显改变。其机制可能与RA抑制松质骨的骨形成,抑制皮质骨骨外膜的骨建造而增强骨内膜的骨重建有关。丹参骨宝对RA致大鼠椎骨生物力学状况有改善作用。

英文摘要：

Aim To investigate the effects of retinoic acid （RA） on induction osteroporosis model rats andpreventive effects of Danshengubao.Methods 4-month-old female Sprague-Dawley rats were given RA at 70 mg·kg^-1·d^-1 and were given Danshengubao at different doses at the same time.All rats were treated by oral gavaged for 28 days.The static and dynamic parameters in cancellous bone of the fifth lumbar vertebrae （LV5） were examined and the dynamic changes of the tibial shaft （Tx） were observed with histomorphometrical analyses; the forth lumbar vertebrae （LV4） was used to perform the compression test.Results Compared with control group, biomechanical properties of LV4, the static parameters （ total tissue area, trabecular area, trabecular perimeter） and the dynamic parameters of LV5 were significantly decreased in RA group.Compared with control group, bone formation of Tx was decreased in periosteal surfaces but enhanced in endocortical surfaces in RA group.Compared with RA group, the biomechanical properties of LV4 were increased significantly in low and medium dose of Danshengubao groups.Conclusions RA can decrease the size and the biomechanical properties of LV, but it can not change the percentage trabecular area. The mechanism may be related to the act that RA can inhibit cancellous bone formation, decrease the modeling of cortical bone in periosteal surfaces and enhance the remolding of cortical bone in endocortical surfaces. Danshengubao can improve biomechanics of LV induced by RA in rats.