骨形态计量学评价低钙对大鼠皮质骨的作用研究

Bone histomorphometric analysis of effects of low calcium on cortical bone in male rats

目的 评价低钙饮食对大鼠皮质骨的影响。方法 3月龄SD普通级雄性大鼠 40只 ,随机分为 5组。第 1、2组饲养 1个月 ,分为正常对照组 (1mol,Ca 1 0 % )和极低钙组VLCD(1mol,Ca0 1 % ) ,余下 3组饲养 3个月 ,分为正常对照组 (3mol,Ca 1 0 % )、极低钙组VLCD(3mol,Ca 0 1 % )和低钙组LCD(3mol,Ca 0 3 % )。各组动物喂养包含对应钙含量的精制饲料 ,处死前进行双荧光标记。实验结束时 ,取左侧胫骨中段行骨形态计量学检测。结果 无论是低钙饮食 1个月 ,还是 3个月 ,无论是极度缺钙 ,还是仅有轻微的钙不足 ,胫骨中段横截面皮质骨始终未出现显著意义的变化 ,但骨内膜骨吸收有增加的趋势。结论 低钙对皮质骨作用不明显 。

Objective To evaluate the effect of low calcium on the cortical bone in male rats by bone histomorphometrical techniques Methods Forty three month old male Sprague Dawley(SD)rats, with a mean weight of (280±22)g, were randomized into five groups Group 1 and group 2 were fed a normal calcium diet as control (Ca 1 0%)and a very low calcium diet (VLCD, Ca 0 1%), respectively, for one month;groups 3 5 were fed a normal calcium diet as Control (Ca 1 0%), a very low calcium diet (VLCD,Ca 0 1%), and a low calcium diet (LCD, Ca 0 3%),respectively for three months All animals received double bone fluorochrome labeling prior to sacrifice At the end of experiment, the left tibiae were harvested for bone histomorphometrical evaluations Results The cortical bone of the mid diaphyseal cross section in VLCD and LCD groups did not change significantly for a diet of either one month or three months, but the bone resorption in endocortical surface tended to increase in calcium restricted groups Conclusion Low calcium has little effect on rat cortical bone, which may be affributed to the sequence of skeletal exploitation by the body