MEASUREMENT OF CALCIUM AND PHOSPHORUS FLUXES DURING LACTATION IN THE RAT
MEASUREMENT OF CALCIUM AND PHOSPHORUS FLUXES DURING LACTATION IN THE RAT
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DOI：
10.1093/jn/119.3.428
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发表时间：
1989-03-01
影响因子：
4.2
通讯作者：
BROMMAGE, R
中科院分区：
文献类型：
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作者：
BROMMAGE, R
新型的，双室代谢笼大鼠构建检查钙和磷通量在哺乳期。在哺乳期大鼠和非哺乳期对照组中进行了4次连续4 d的平衡研究。哺乳期大鼠有显着更高的肠道钙和磷的吸收，这是由于增加的食物消耗和这些元素的吸收分数升高。在哺乳期尿钙排泄量减少，而尿磷排泄量不变。内源性粪便钙排泄（通过输注45 Ca和粪便45 Ca含量除以尿45 Ca比活度测定）在哺乳和非哺乳大鼠中相似。在一项单独的研究中，幼仔摄入的钙平均保留率为96%。因此，在幼犬胴体钙含量的差异之间的第1天和17日的年龄被假定为等于96%的钙转移率进入牛奶。类似的计算应用于P.牛奶转移率被确定为126和99毫克/天的钙和磷，分别。 这些计算表明，19%的钙转移到牛奶来自母体骨骼与母体饮食提供其余的钙。这项研究提供了第一个全面的分析，在大鼠哺乳期间发生的钙和磷通量的变化。
Novel, two-compartment metabolic cages for rats were constructed to examine Ca and P fluxes during lactation. Four consecutive balance studies of 4 d each were performed in lactating rats and nonlactating controls. Lactating rats had dramatically higher intestinal absorptions of Ca and P resulting from both increased food consumption and elevated fractional absorptions of these elements. Urinary Ca excretion was reduced during lactation whereas urinary P excretion was unchanged. Endogenous fecal Ca excretion (determined by infusing 45Ca and dividing fecal 45Ca content by urinary 45Ca specific activity) was similar in lactating and nonlactating rats. In a separate study, pup retention of ingested Ca averaged 96%. Therefore, the difference in pup carcass Ca content between d 1 and 17 of age is assumed to equal 96% of the Ca transfer rate into milk. Similar calculations were applied to P. Milk transfer rates were determined to be 126 and 99 mg/d for Ca and P, respectively. These calculations indicate that 19% of the Ca transferred to milk was derived from the maternal skeleton with the maternal diet supplying the remaining Ca. This study provides the first comprehensive analysis of the alterations in Ca and P fluxes that occur during lactation in the rat.