Effect of dietary Calcium source to improvement of bone metabolism.

乳清钙对去卵巢骨质疏松模型大鼠骨代谢的影响本研究探讨了乳清作为钙源在饲料中的生物利用度，并与CaCO_3和CaHPO_4作比较。然后将大鼠分为乳清组、CaCO3组和CaHPO4组，进行钙平衡、骨密度测定和骨断裂性能测定。结果表明，三组间血钙水平、食物效率比和体重增加无显著差异。乳清钙组的尿钙排泄量高于CaCO3组和CaHPO4组。与CaCO3组相比，乳清组和CaHPO4组的股骨断裂性能和显微密度参数Sigma GS、Sigma GS/D、GSmin、GSmax均增加。乳清组上述各项指标均略高于磷酸二氢钙组(P<0.05)。这些结果清楚地表明，乳清作为一种钙源，对增加骨骼强度有有益的作用。

Effects of Whey Ca on Bone Metabolism in Ovariectomized Osteoporosis Model RatsIn this study, we investigated the bioavailability of whey in diet as a Ca source, compared to CaCO_3 and CaHPO_4.5-weeks-female rats were ovariecotomized, and then they were fed on the low Ca diet(Ca:0.01%) for 27days. After that, these rats were divided into three groups, whey, CaCO_3 and CaHPO_4. They were estimated Ca balance, microdensitometry and breaking properties of bone. As a result, there were no significant differences in serum Ca levels, food efficiency ratio and body weight gain between those three groups. On the other hand, in whey Ca diet group, the urinary Ca excretion is higher than that of CaCO_3 and CaHPO_4 diet groups. And in whey and CaHPO_4 diet groups, the femur breaking properties and the parameters of micro densitometry, SIGMA GS, SIGMA GS/D, GSmin, GSmax, increased compared to CaCO_3 diet group. And those parameters of whey diet group were a little higher than that of CaHPO_4 diet group (not significant). These results clearly suggest that the whey, as a Ca source, has a beneficial effect on increasing bone strength.