中文摘要：

目的探讨环磷酰胺致大鼠骨质疏松模型中皮质骨的特点,观察中、低剂量阿司匹林的预防作用,并与碳酸钙维D进行比较。方法 3月龄SD大鼠灌服环磷酰胺4.5 mg.kg-1.d-1造模,同时给予中、低剂量阿司匹林和碳酸钙维D进行预防,用药时间为15 d。实验结束后,骨组织形态计量学观测左侧胫骨中段骨磨片的动静态参数。同时取大鼠右侧股骨进行骨生物力学检测,随后检测骨钙、磷、镁和羟脯氨酸含量。结果环磷酰胺通过抑制骨形成活性,使大鼠皮质骨骨髓腔扩大,管壁变薄,骨有机质和无机物等比例丢失,骨质量降低。中、低剂量的阿司匹林可有效促进骨形成,对抗环磷酰胺大鼠的骨丢失,效果与碳酸钙维D相当。低剂量的阿司匹林对于环磷酰胺大鼠骨质量的改善作用最佳。结论中、低剂量的阿司匹林均可有效地促进骨形成,预防环磷酰胺所诱导的大鼠低转换型骨质疏松。

英文摘要：

Aim To study osteoporosis of rats induced by cyclophosphamide in cancellous bone,and investigate the preventive effects of middle and low dose aspirin on rats.And to compare the preventive effects with those of CaCO3 and VD.Methods Cyclophosphamide at the dose of 4.5 mg·kg-1·d-1 was given to the rats orally for 15 days while CaCO3 and VD,middle dose aspirin,and low dose aspirin were given to cyclophosphamide-treated rats orally.At the experimental endpoint,the undecalcified longitudinal proximal tibia was cut for osteoclasts analysis and for the cancellous bone histomorphometric and fluorochrome labeling analysis.The fifth lumbar vertebrae（LV5）was used to perform the compression test.Then the hydroxyproline,Ca,P,Mg of bone were tested.Results Cyclophosphamide caused compact bone loss by significantly inhibiting bone formation,and decreasing biomechanics property,bone mineral and hydroxyproline on femur of rats.Two different doses of aspirin could enhance bone formation.The preventive effect of aspirin on osteoporosis was equal to that of CaCO3 and VD.Effect of low dose aspirin to increase the quality of CP-treated rat′s femur was the best.Conclusion Different doses of aspirin can aslo enhance bone formation.