Vitamin D status and brush border membrane vesicles: 1,25-dihydroxyvitamin D3 induced destabilization.
Vitamin D status and brush border membrane vesicles: 1,25-dihydroxyvitamin D3 induced destabilization.
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维生素 D 状态和刷状缘膜囊泡：1,25-二羟基维生素 D3 诱导不稳定。
DOI：
10.1002/jbmr.5650010402
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Norman,AW
中科院分区：
文献类型：
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作者：
Putkey,JA;Nemere,I;Norman,AW
用纯化的鸡十二指肠刷状缘膜囊（BBMV）研究了维生素D对小肠Ca ~（2+）转运和膜稳定性的影响。通过在Triton X-100存在下乳过氧化物酶对核心材料肌动蛋白的可及性增加9倍来判断，BBMV制备物是正面朝外的。从维生素D缺乏的小鸡新鲜制备的BBMV支持钠依赖性葡萄糖转运和Ca 2+摄取。在体内用1，25（OH）2D 3处理导致Ca 2+摄取的Vmax从2.2增加到3.9 nmol/min/mg蛋白质。钙摄取的Km（0.9 mM）与鸡的维生素D状态无关。如果将来自维生素D充足的小鸡的大多数BBMV在0-4°C下保持2至24小时，则其不稳定并且不能支持钠依赖性葡萄糖摄取或Ca 2+摄取。在40个独立的实验中，80%的来自维生素D充足的小鸡的膜显示出不稳定的特征，而所有对照膜中只有24%表现出缺乏活力。
Purified chick duodenal brush border membrane vesicles (BBMV) were used to assess the effect of vitamin D on intestinal Ca2+transport and membrane stability. BBMV preparations are right‐side‐out as judged by a nine‐fold increase in accessibility of lactoperoxidase to core material actin in the presence of Triton X‐100. Freshly prepared BBMV from vitamin D‐deficient chicks support both sodium‐dependent glucose transport and Ca2+uptake.In vivotreatment with 1,25(OH)2D3results in an 85% increase in theVmaxof Ca2+‐uptake from 2.2 to 3.9 nmol/min/mg protein. TheKmof Ca2+‐uptake (0.9 mM) is independent of the vitamin D status of the chick. The majority of BBMV derived from vitamin D‐replete chicks were destabilized and rendered incapable of supporting either sodium‐dependent glucose uptake or Ca2+uptake if they were held at 0–4°C for 2 to 24 h. In 40 separate experiments, 80% of membranes derived from vitamin D‐replete chicks showed characteristics of destabilization, whereas only 24% of all control membranes exhibited a lack of viability.