Alteration in water channel AQP-2 by removal of AVP stimulation in collecting duct cells of dehydrated rats.
Alteration in water channel AQP-2 by removal of AVP stimulation in collecting duct cells of dehydrated rats.
复制标题
去除脱水大鼠集合管细胞中 AVP 刺激后水通道 AQP-2 的改变。
DOI：
10.1152/ajprenal.1997.272.2.f183
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
T. Saito
中科院分区：
文献类型：
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作者：
T. Saito;S. Ishikawa;S. Sasaki;N. Fujita;K. Fushimi;K. Okada;K. Takeuchi;A. Sakamoto;S. Ookawara;T. Kaneko;F. Marumo;T. Saito
脱水增加了集合管水通道蛋白2（AQP-2）的表达，并使AQP-2从集合管细胞的胞质小泡移位到顶端质膜。我们确定是否突然减少循环精氨酸加压素（AVP）给予过量的水影响水通道蛋白-2 mRNA的表达和水通道蛋白-2在脱水大鼠集合管细胞的亚细胞定位。72 h禁水使大鼠血浆AVP水平升高至3.1 pg/ml，AQP-2 mRNA表达增加336%，而40 ml/kg饮水负荷可使其消失。水负荷后20 min，AQP-2 mRNA表达抑制率达50%。免疫组化和电镜观察显示，脱水72 h大鼠集合管细胞的顶端边缘可见AQP-2的表达。AQP-2在强迫水处理后1h弥散性移位到胞浆中。这些结果表明AVP对AQP-2 mRNA的表达起开关调节作用，且AQP-2的大部分表达受集合管细胞穿梭循环的调节。
Dehydration increased the expression of aquaporin of collecting duct (AQP-2) and translocated AQP-2 to the apical plasma membranes from cytoplasmic vesicles of collecting duct cells. We determined whether the abrupt decrease in circulating arginine vasopressin (AVP) by giving excess water affects the expression of AQP-2 mRNA and subcellular localization of AQP-2 in collecting duct cells of the dehydrated rats. The 72-h water deprivation increased plasma AVP levels to 3.1 pg/ml and the expression of AQP-2 mRNA by 336% in rats, which were concomitantly abolished by the 40 ml/kg oral water load. A 50% inhibition ofAQP-2 mRNA expression was obtained with 20 min after the forced water load. In immunohistochemistry and electron microscopy, the AQP-2 was manifestly present around the apical edge of collecting duct cells in the 72-h dehydrated rats. The AQP-2 was diffusely translocated into the cytoplasm 1 h after the forced water administration. These results indicate that AVP plays the on-off regulation of AQP-2 mRNA expression and that a majority of AQP-2 is regulated by the shuttle recycling in the collecting duct cells.