目的:研究局部注射唑来膦酸和rhBMP-2对兔骨质疏松模型血清生化指标及骨小梁生长速率的影响。方法30只5月龄雌性新西兰大白兔,随机选取24只摘除双侧卵巢制造骨质疏松模型,另外6只切开暴露卵巢后即关腹,作为假手术对照组。造模成功后,24只骨质疏松兔按注射药物不同分为BMP组(rhBMP-2)、ZOL组(唑来膦酸)、B+Z组(rhBMP-2+ZOL)、空白对照组(生理盐水)及假手术组,每组6只动物。分别在注射后当天、2周、4周、6周、8周、10周、12周,由兔耳缘静脉取血,分离血清,使用相应试剂盒检测血清碱性磷酸酶( ALP)、抗酒石酸酸性磷酸酶( TRACP)活性;同时应用四环素-钙黄绿素荧光标记在第6周、第12周处死取材,观察并测量骨小梁生长速率。结果①注射后第4周,BMP、B+Z组ALP活性均明显高于ZOL组和NON组(P<0.05);从第6周开始,BMP与B+Z组的ALP活性与假手术组均无明显差异(P>0.05);②在第8、10周,B+Z组TRACP活性明显低于假手术组( P<0.05);ZOL和B+Z组TRACP活性较早即开始下降,并且与BMP组相比下降更快(P<0.05)。③BMP组骨小梁生长速率在各个时间点均明显高于其他三组(P<0.05)。结论 rhBMP-2+ZOL联合应用,能够更好地抑制破骨细胞的骨吸收作用,而rhBMP-2则能够增强成骨细胞的成骨作用,提高骨小梁的生长速率。
Objective To study the effect of local injection of zoledronic acid and rhBMP-2 on the serum biochemical index and trabecular growth rate in rabbit osteoporosis model.Methods Thirty 5-month-old female New Zealand white rabbits were randomly selected to be ovariectomized to make osteoporosis model ( n=24 ) or to be sham operated as control ( n=6 ) .After successful modeling, the 24 rabbits were randomly divided into BMP group, ZOL group, B+Z group ( rhBMP-2+ZOL) , and NON ( sham) group.Six rabbits were in each group.Serum was collected from the ear vein at the day of injection and 2, 4, 6, 8, 10, and 12 weeks after the injection, respectively.The activities of alkaline phosphatase ( ALP ) and tartrate-resistant acid phosphatase ( TRACP) were detected using the corresponding kit.The rabbits were killed at 6 weeks and 12 weeks, respectively. Tetracycline-calcein labeling was used to measure the growth rate of trabeculae.Results 1) After 4 weeks of the injection, the activity of ALP in BMP group and B+Z group were significantly higher than that in ZOL group and NON group (P〈0.05).From 6 weeks on, the activity of ALP in BMP group and B+Z group was not different comparing to that in the sham group (P〉0.05). 2) At 8 and 10 weeks, the activity of TRACP in B +Z group was significantly lower than that in sham group (P 〈0.05). Meanwhile, the activity of TRACP in ZOL group and B+Z group declined earlier and faster than that in BMP group (P〈0.05). 3) The growth rate of bone trabeculae in BMP group was significantly higher than that in other groups at all time points (p〈0.05)."nbsp;Conclusion Application of rhBMP-2 combined with ZOL can better inhibit bone resorption of osteoclasts.rhBMP-2 can increase the growth rate of bone trabeculae in osteoporosis rabbits.