The Role of Vitamin D3 Metabolites on the Regulation of Carbonic Anhydrase Activity in the Chorionic Epithelium of the Chick Embryo
The Role of Vitamin D3 Metabolites on the Regulation of Carbonic Anhydrase Activity in the Chorionic Epithelium of the Chick Embryo
复制标题
维生素D3代谢物对鸡胚胎绒毛膜上皮碳酸酐酶活性的调节作用
DOI：
10.1111/j.1749-6632.1984.tb12374.x
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
L. Sitwell
中科院分区：
文献类型：
--
作者：
R. Narbaitz;S. Kacew;L. Sitwell
鸡胚从蛋壳中获取大量的钙，以使其骨骼矿化。矿物的再吸收（碳酸钙）通过绒毛膜上皮发生，并且碳酸酐酶在此过程中的作用由以下事实表明：酶活性：（a）在绒毛尿囊膜的赤道区较大，直接参与吸收;（b）随着年龄的增长而增加，并在吸收也处于峰值时达到峰值;（B）随着年龄的增长而增加，并在吸收也处于峰值时达到峰值;和（c）已经在细胞化学上定位于“绒毛腔”细胞中，由于它们的分布、出现的年龄和超微结构特征，这些细胞被怀疑参与壳的再吸收。13当注射到胚胎中时，1，25（OH）2维生素D3产生高钙，可能通过增加从壳的再吸收。放射自显影研究表明富含碳酸酐酶的绒毛腔细胞是1，25（OH），D3的靶。这表明维生素D代谢物通过刺激这些细胞中的碳酸酐酶活性而产生高钙血症。目前的实验计划是为了测试这一假设。
The chick embryo obtains large amounts of calcium from the egg-shell in order to mineralize its skeleton. Resorption of the mineral (calcium carbonate) takes place through the chorionic epithelium and a role of carbonic anhydrase in this process is suggested by the facts that the enzymatic activity: (a) is greater in the equatorial zone of the chorioallantoic membrane, which is directly involved in resorption; (b) increases with age and reaches a peak at the time in which resorption is also at a peak; and (c) has been localized cytochemically in “villus-cavity’’ cells, which are suspected to be involved in shell resorption because of their distribution, age of appearance, and ultrastructural characteristics.13 When injected into the embryo, 1,25(OH)2 vitamin D3 produces hypercalcernia, probably by increasing resorption from the shelL4 Autoradiographic studies have shown that the carbonic anhydrase-rich villus-cavity cells are targets for 1 ,25(0H),D3s. and this has suggested that the vitamin D metabolite produces the hypercalcemia by stimulating carbonic anhydrase activity in these cells. The present experiments have been planned in order to test this postulate.