抗利尿激素通过抑制钠/氢交换降低远端肾单位上皮细胞（A6）内的细胞内pH值。

Antidiuretic hormone decreases the intracellular pH in distal nephron epithelium (A6) by inhibiting Na+/H+ exchange.

Doi Y, Marunaka Y

Division of Respiratory Research, Hospital for Sick Children Research Institute, University of Toronto Faculty of Medicine, Ontario, Canada.

Gen Pharmacol. 1995 Jul;26(4):723-6. doi: 10.1016/0306-3623(94)00254-k.

Abstract

To clarify the effect of arginine vasotocin (AVT) on intracellular pH (pHi) of A6 cells (an amphibian renal cell line), we measured pHi with a single-cell fluorescent imaging system in an HCO3(-)-nominally-free medium. 2. AVT (40 mU/ml) significantly decreased pHi from 7.44 +/- 0.11 to 7.19 +/- 0.22 (mean +/- SE) by inhibiting the Na+/H+ exchanger. 3. A membrane-permeable analogue of cAMP, dibutyryl cAMP (1 mM), significantly decreased pHi from 7.40 +/- 0.02 to 7.17 +/- 0.02, a response similar to that of AVT. 4. These data indicate that, in A6 cells, AVT suppresses the Na+/H+ exchanger via a cAMP-dependent pathway and the Na+/H+ exchanger maintains pHi under HCO3(-)-nominally-free conditions.

摘要

为阐明精氨酸血管加压素（AVT）对A6细胞（一种两栖类肾细胞系）细胞内pH（pHi）的影响，我们在名义上无HCO3(-)的培养基中使用单细胞荧光成像系统测量pHi。2. AVT（40 mU/ml）通过抑制Na+/H+交换体，使pHi从7.44±0.11显著降至7.19±0.22（平均值±标准误）。3. 一种cAMP的膜通透性类似物，二丁酰cAMP（1 mM），使pHi从7.40±0.02显著降至7.17±0.02，该反应与AVT相似。4. 这些数据表明，在A6细胞中，AVT通过cAMP依赖性途径抑制Na+/H+交换体，并且在名义上无HCO3(-)的条件下，Na+/H+交换体维持pHi。