Abstract

Changes in bone mineral content of calcium (Ca), phosphorous (P), magnesium and potassium for male and female Wistar rats during their development from 3 weeks old to adulthood (27 weeks old) were measured. Bone mineral content was related to areal bone mineral density (BMD) which was measured in vivo at the femoral neck using a calibrated X-ray transmission system to obtain basal curves as a function of the age of the specimen. Diagnostic curves were built to determine low BMD (osteopaenia) and osteoporosis in female rats fed a Ca-depleted diet (50%) based on the obtained data and the criteria established by the World Health Organization. Bone mineral content is directly related to sex and age, but P did not change throughout the experimental period. P content did not exhibit significant changes with growing, while Ca was greatest in male rats, producing significant differences in the Ca:P ratio. Male rats reach the Ca:P ratio peak before female rats. However, areal BMD does not follow the same trend. On the other hand, osteoporosis produced a 45% decrease in this parameter for young and mature adults. These results make Z-score values available to diagnose bone-mass losses and hence the possibility of improving the conditions of non-contact measurement of BMD in vivo. This technique can be used for future experiments with Wistar rats.

摘要

测量了雄性和雌性 Wistar 大鼠从 3 周龄到成年（27 周龄）发育过程中钙 (Ca)、磷 (P)、镁和钾的骨矿物质含量的变化。骨矿物质含量与面积骨矿物质密度 (BMD) 相关，骨矿物质密度 (BMD) 在股骨颈使用校准的 X 射线透射系统在体内测量，以获得作为样本年龄的函数的基础曲线。根据获得的数据和世界卫生组织制定的标准，建立诊断曲线以确定喂食钙耗尽饮食 (50%) 的雌性大鼠的低 BMD（骨质减少）和骨质疏松症。骨矿物质含量与性别和年龄直接相关，但 P 在整个实验期间没有变化。P含量随生长发育无明显变化，而雄性大鼠Ca含量最高，Ca:P 比率产生显着差异。雄性大鼠在雌性大鼠之前达到 Ca:P 比率峰值。然而，面积 BMD 并不遵循相同的趋势。另一方面，骨质疏松症使年轻人和成熟成年人的这一参数降低了 45%。这些结果使Z值可用于诊断骨量损失，因此有可能改善体内 BMD 的非接触测量条件。该技术可用于未来的 Wistar 大鼠实验。