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Updated: Feb 12, 2026
Development of Human Renal Tubular Epithelial Cell Primary Cultures in Monolayers and Three-Dimensional Conditions
Published on: June 13, 2025
Endothelin-1 enhances the activity of Na+/Ca2+ exchanger type 1 in renal epithelial cells
Satomi Kita1, Takeshi Katsuragi, Takahiro Iwamoto
1Department of Pharmacology, School of Medicine, Fukuoka University, Fukuoka, Japan.
Abstract:
The Na+/Ca2+ exchanger, an ion transporter across the plasma membrane, is considered to play a role in calcium reabsorption in the renal nephron. We found that endothelin-1 enhanced Na+/Ca2+ exchange activity in renal epithelial LLC-PK1 cells. Treatment with endothelin-1 increased concomitantly the phosphorylation of Na+/Ca2+ exchanger type 1 (NCX1). Chelerythrine and prolonged exposure to phorbol 12-myristate 13-acetate abolished the activation of NCX1 induced by endothelin-1. To further analyze the activation mechanism of NCX1 by endothelin-1, we examined the effects of endothelin-1 in LLC-PK1 cells expressing NCX1 with mutated exchanger inhibitory peptide regions, which have either no Na+-dependent inactivation (XIP-4YW) or accelerated inactivation (F223E). The exchange activities in LLC-PK1 cells expressing wild-type NCX1 or F223E were stimulated by endothelin-1, but not in cells expressing XIP- 4YW. These results suggest that endothelin-1 activates NCX1 in renal epithelial cells through the pathway of protein kinase C and the process related to Na-dependent inactivation.
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