Amelioration of biomechanical property of cortical bone in osteoporotic model rats with the kidney tonifying compound of traditional Chinese medicine / 中国组织工程研究

ABSTRACT

BACKGROUND: The biomechanical property(BP) of the bone is decided by its geometric structure and component material. Merely pursuing increase of the bone mineral density(BMD) might lead to deterioration of bone BP.However at present, some researohes on therapeutic action on osteoporosis emphasize excessively medical influence to BMD, and the change in the holistic BP of the bone in osteoporotic zone and its mechanism still need to investigate deeply.OBJECTIVE: To probe into the action and its mechanism of "the kidney tonifying compound of the Traditional Chinese Medical (TCM) "on BP of cortical bone in ovariectomized osteoporotic model rats.DESIGN: Completely randomized controlled experiment based on experimental animals.SETTING: Laboratory of Biomedical Engineering, Luoyang Hospital and Institute of Traditional Chinese Orthopedics and Traumatology in Henan Province.MATERIALS: The experiment was completed from November 2000 to July 2001 at Research Laboratory of Biomedical Engineering,Luoyang Institute of Traditional Chinese Orthopedics and Traumatology of Henan Province. The healthy Wistar female rats aged 10 months,weighing(350±20) g.METHODS: Fifty Whistar female rats aged 10 months were randomly divided into 5 groups: the normal, model, premarin-treated, xianling gubao-treated and migu capsule-treated with 10 in each group. The normal group was only given sham operation and the other four groups were ovariectomized. The rats after operation were fed normally for ninety days.Since the 91st day after operation,the rats had been given the medicines for 90 days and then killed. The thighbones were taken out,then BMD,femoral geometry sizes and BP were determined.MAIN OUTCOME MEASURES: ① The primary sequel was the comparison of the parameters of femoral BP. ② The secondary sequel was the changes in parameters of femoral geometric structure, area of cortical bone and BMD of every midsectional fomur.RESULTS: Femoral BP worsened significantly,its mechanical intensity reduced,its external diameter diminished,cortical bone area decreased and femoral BMD lowered in osteoporotic model rats. In comparison with the above,in "the kidney tonifying compound ofTCM " groups(migu capsule group and xianling gubao group) femoral BP raised significantly, its mechanical intensity advanced,its external diameter augmented,cortical bone area aggrandized and femoral BMD enhanced.CONCLUSION: "The kidney tonifying compound of TCM" can improve BP of the cortical bone(thighbone) in ovariectomized osteoporosis rats. Its primary mechanism of action is that the TCM compound prescription could enhance"the mechanism of biomechanical response and regulation"(MBRR) of macrostructure of cortical bone,consequently increase femoral external diameter,aggrandize cortical bone area and enhance BMD in ovariectomized rats.