ELEVATED SERUM LEVELS OF 1-ALPHA, 25-DIHYDROXYCHOLECALCIFEROL IN LACTATING RATS
ELEVATED SERUM LEVELS OF 1-ALPHA, 25-DIHYDROXYCHOLECALCIFEROL IN LACTATING RATS
复制标题
DOI：
10.1038/267630a0
复制
发表时间：
1977-01-01
期刊：
影响因子：
64.8
通讯作者：
HAUSSLER, MR
中科院分区：
文献类型：
--
作者：
BOASS, A;TOVERUD, SU;HAUSSLER, MR
哺乳对钙代谢的调节提出了挑战。由于钙转移到乳汁中的速率很高，因此食用商业储备饲料的哺乳期大鼠保持降低的血清钙水平1。对钙的需求增加似乎主要通过增加肠道对钙的吸收来满足（参考文献1）。由于维生素D对钙代谢的调节很重要，特别是在哺乳期2，并且由于活性代谢物1 α，25-二羟基维生素D3（1α，25-（OH）2D 3）的循环水平似乎根据钙需要3进行调节，因此我们通过放射受体结合试验测定了维生素D喂养的哺乳期大鼠中1α，25-（OH）2D 3的血清水平。我们在这里报告说，这些水平比非哺乳期对照组高出两到四倍。在哺乳期剥夺维生素D的大鼠没有表现出代谢物血水平升高，并出现明显的低钙血症，因此表明1α，25-（OH）2D 3血水平升高对哺乳期钙代谢的重要性。
LACTATION represents a challenge to regulation of calcium metabolism. Because of the high rate of calcium transfer to the milk, the lactating rat consuming a commercial stock diet maintains a reduced serum Ca level1. The increased need for Ca seems to be met primarily by increased intestinal absorption of Ca (ref. 1). Since vitamin D is important for regulation of Ca metabolism, particularly during lactation2, and since the circulating level of the active metabolite lα,25-dihydroxyvitamin D3(1α,25-(OH)2D3) seems to be regulated according to Ca needs3, we determined by radioreceptor binding assay the serum levels of 1α,25-(OH)2D3in vitamin D-fed lactating rats. We report here that these levels are two- to fourfold higher than those of non-lactating controls. Rats deprived of vitamin D during lactation fail to show elevated metabolite blood levels and develop marked hypocalcaemia, thus indicating the importance of the elevated blood level of 1α,25-(OH)2D3for Ca metabolism during lactation.