钙剂及甲基睾丸酮对老龄雄性大鼠股骨计量形态学及骨矿的影响

Effect of calcium and methyltestosterone complement on the femoral histomorphology and mineral level of aged osteoporostic rats

目的探讨钙剂、甲基睾丸酮对老龄雄性大鼠骨质疏松的作用效果及其发生机制,为老年男性骨质疏松的临床干预寻找理论依据。方法26只新生雄性Sprague Dawley(SD)大鼠,按体重随机分成老龄对照组、青年对照组、葡萄糖钙组(2.5mg/kg·d)及甲基睾丸酮组(25mg/kg·d),同等条件下饲养,青年对照组饲养至6个月,其余3组饲养至22个月后,对其中两组开始分别连续给药92d。经处理后,取左侧股骨,用双光子骨密度仪测定骨密度;北航半自动彩色图像分析系统进行骨组织形态计量学分析,测量骨小梁体积、骨小梁宽度、骨小梁间隔、骨皮质厚度;原子吸收分光光度法及钼兰比色法检测各组大鼠骨钙、骨磷的浓度。结果22月龄雄性大鼠可作为自然衰老骨质疏松的实验模型;与老龄对照组比较,葡萄糖酸钙组和甲基睾丸酮组大鼠股骨密度、骨小梁体积、骨小梁宽度及皮质厚度增加(P<0.05),骨小梁间隙缩小(P<0.05),骨矿化水平提高(P<0.05)。结论补充钙剂和甲基睾丸酮可增加股骨密度及骨矿化水平,促进老龄雄性大鼠股骨形态学的改善。

Objective To explore the preventive effects of calcium and methyltestosterone on femoral histomorphology and mineral levels and the related mechanisms in the aged male osteoporostic rats which would provide the theoretic basis for the intervention of aged male osteoporosis. Methods 26 Sprague Dawley （SD） male rats, one month old, were randomized into four groups： （1） Aged control group （AC group）, （2） Youth control group （YC group）, （3） Calcium complement group （Ca group） and, （4） Methyhestosterone complement group （T group）. 8 rats were fed and sacrificed at 6 months as youth control group. The other 18 were fed fill 22 months, and two groups were administered calcium gluconate （2.5 mg/kg body weight, daily）, methyhestosterone （25 mg/kg body weight, daily） for 92 days respectively, whereas the AC group received daily diet. Bone mineral density （BMD）, bone calcium, bone phosphorus, bone histomorphology in Femur were measured with respective methods. Results The 22-month male rats can be considered as natural osteoporosis model. The BMD and bone mineral levels in femur of Ca group rats and T group rats were higher than those of the AC rats P 〈 0.05 ）, but lower than those of the YC rats （P 〈 0.05）. Compared with AC rats, rats in Ca group and T group had higher bone trabecular area, trabecular width, cortical thickness （P 〈 0.05 ） and lower trabecular space （P 〈 0.05 ）. Conclusion Calcium and Methyhestosterone can increase the bone mineral level of femur and improve the femoral microstructure status in aged male osteoporostic rats.