Evidence for multiple effects of vitamin D3 on calcium absorption: response of rachitic chicks, with or without partial vitamin D3 repletion, to 1,25-dihydroxyvitamin D3.
Evidence for multiple effects of vitamin D3 on calcium absorption: response of rachitic chicks, with or without partial vitamin D3 repletion, to 1,25-dihydroxyvitamin D3.
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维生素 D3 对钙吸收的多重影响的证据：有或没有部分维生素 D3 补充的佝偻病雏鸡对 1,25-二羟基维生素 D3 的反应。
DOI：
10.1073/pnas.79.24.7939
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发表时间：
1982
影响因子：
11.1
通讯作者：
Fullmer,CS
中科院分区：
文献类型：
--
作者：
Wasserman,RH;Brindak,ME;Meyer,SA;Fullmer,CS
研究了维生素D3或1,25-二羟基维生素D3 [1,25(OH)2D3]或两者对钙吸收、维生素d诱导的钙结合蛋白（CaBP）和磷脂代谢之间关系的影响。将1,25(OH)2D3注入d3缺陷雏鸡心内，在2 ~ 4小时后刺激钙吸收并诱导CaBP合成。将1,25(OH)2D3注射到部分补充D3的雏鸡体内，可以观察到早期钙吸收的增加，而十二指肠黏膜中已经存在的CaBP浓度没有显著变化。其他早期事件是肠组织钙吸收增加和磷脂代谢改变。这些和其他观察结果支持了至少两个阶段的钙吸收受到125 (OH)2D3的影响——钙在刷状边界的渗透，以及钙在细胞内和细胞外的转移。第一阶段对1,25(OH)2D3的反应比第二阶段更快，与磷脂代谢的变化相关，并且可能不依赖于从头合成蛋白质。第二阶段与CaBP合成相关，因此依赖于蛋白质合成。第一阶段或第二阶段都可以构成钙吸收的限制步骤。
The effects of vitamin D3 or 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], or both, on the relationship among calcium absorption, vitamin D-induced calcium-binding protein (CaBP), and phospholipid metabolism were examined. When 1,25(OH)2D3 was injected intracardially into D3-deficient chicks, both the stimulation of calcium absorption and the induction of the synthesis of CaBP occurred 2-4 hr later. When 1,25(OH)2D3 was injected into chicks partially repleted with D3, an earlier increase in calcium absorption was observed without a significant change in the concentration of CaBP already present in the duodenal mucosa. Other early events were an increased uptake of calcium by the intestinal tissue and an alteration in phospholipid metabolism. These and other observations support the proposal that at least two phases of calcium absorption are influenced by 1,25(OH)2D3--permeation of calcium across the brush border, and transfer of calcium through and out of the cell. The first phase responds more rapidly to 1,25(OH)2D3 than does the second phase, correlates with changes in phospholipid metabolism, and might not be dependent on de novo protein synthesis. The second phase correlates with CaBP synthesis and therefore is dependent on protein synthesis. Either the first phase or the second phase can constitute the limiting step in calcium absorption.