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.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.