Increases in cellular sodium concentration by arginine vasopressin and endothelin in cultured rat glomerular mesangial cells.
Increases in cellular sodium concentration by arginine vasopressin and endothelin in cultured rat glomerular mesangial cells.
复制标题
精氨酸加压素和内皮素增加培养的大鼠肾小球系膜细胞中的细胞钠浓度。
作者：
S. Ishikawa;K. Okada;T. Saito
The present study was undertaken to determine whether arginine vasopressin (AVP), angiotensin-II, and endothelin (ET) increase the cellular sodium concentration ([Na+]i) in cultured rat glomerular mesangial cells. [Na+]i was measured using the fluorescence indicator dye sodium-binding benzofuran isophthalate. These three vasoconstrictor hormones increased cellular free calcium ([Ca2+]i) and [Na+]i in a dose-dependent manner ([Na+]i: basal, 11.5; 10(-7) M AVP, 20.5; 10(-7) M angiotensin-II, 13.8; and 10(-7) M ET, 21.2 mM). The mobilization of [Ca2+]i was faster than that of [Na+]i. The AVP-induced increase in [Na+]i was completely blunted by the potent V1 antagonist d(CH2)5Tyr(Me)AVP. Vasoconstrictor hormones produced a biphasic cellular pH (pHi) change, characterized by a transient acidification, followed by a sustained alkalinization. The Ca(2+)-free condition markedly reduced AVP- and ET-induced increases in [Ca2+]i and [Na+]i and biphasic changes in pHi. In the Na(+)-free state, the hormonally mobilized [Ca2+]i was significantly enhanced. Basal [Na+]i decreased to below 3 mM, and there was little increase in [Na+]i after the addition of vasoconstrictor hormones, suggesting that the source of [Na+]i is extracellular space. Only early acidification was obtained in the absence of a sustained alkalinization. The [Na+]i mobilization was closely related to the biphasic change in pHi. These results indicate that AVP, ET, and angiotensin-II increase [Na+]i in glomerular mesangial cells, and that the early mobilization of [Na+]i depends on Na+/Ca2+ exchange, and the sustained phase depends on Na+/H+ exchange. The hormonally mobilized [Ca2+]i is essential for the activation of Na+/H+ exchange, and an increase in [Na+]i is suggested to play an important role in cellular alkalinization.
DOI：
10.1016/s0021-9258(19)47321-3
发表时间：
1989-11
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Akwasi MintaS;Roger Y. TsienO
通讯作者：
Akwasi MintaS;Roger Y. TsienO
细胞外和细胞内 pH 对精氨酸加压素血管作用的影响。
DOI：
10.1152/ajprenal.1991.260.1.f39
发表时间：
1991
期刊：
The American journal of physiology
影响因子：
--
作者：
Okada,K;Tsai,P;Briner,VA;Caramelo,C;Schrier,RW
通讯作者：
Schrier,RW