Angiotensin II stimulates the Na+/H+ exchanger in human umbilical vein endothelial cells via AT1 receptor

Citation
A. Muscella et al., Angiotensin II stimulates the Na+/H+ exchanger in human umbilical vein endothelial cells via AT1 receptor, LIFE SCI, 65(22), 1999, pp. 2385-2394
Citations number
29
Categorie Soggetti
Biochemistry & Biophysics
Journal title
LIFE SCIENCES
ISSN journal
00243205 → ACNP
Volume
65
Issue
22
Year of publication
1999
Pages
2385 - 2394
Database
ISI
SICI code
0024-3205(19991022)65:22<2385:AISTNE>2.0.ZU;2-H
Abstract
Angiotensin II (Ang II) has an important role in cardiovascular regulation and in the control of electrolyte balance, and its role in the regulation o f Na+ transcellular movements through its actions on the activity of Na+/K ATPase is well documented. We showed previously that human umbilical vein endothelial cells (HUVEC) express the Ang II type 1 (AT1) receptor, which m ediates Ang II modulation of Na+/K(+)ATPase activity (1). We here investiga te the effects of Ang II on the activity of the Na+/H+ exchanger in HUVEC. When compared with controls, incubation of HUVEC for 20 min with different concentrations of Ang II provoked significant increases in Na+/H+ activity. The stimulation was dose dependent between 1 and 10 nM Ang II and varied w ith time of incubation up to 20 min. The maximal response, obtained with 10 nM Ang II after 20 min treatment, resulted in a 65% increment in Na+/H+ ac tivity. Preincubation of HUVEC with 10 mu M DuP753 blocked Na+/H+ activatio n by Ang II. These results suggest that the effects of Ang II on both the N a+/K(+)ATPase and the Na+/H+ exchanger may increase the transendothelial fl ux of Na+ and are mediated by the AT1 receptor.