title: Amlodipine increases endothelial nitric oxide release by modulating binding of native eNOS protein complex to caveolin-1.
abstract: Amongst calcium channel blockers, amlodipine is known to have unique cardioprotective activities likely attributable to its capacity to increase nitric oxide (NO) release from endothelial cells (EC). Because endothelial NO synthase (eNOS), the main source of NO in EC is known to be inhibited by caveolin-1 (Cav-1), the purpose of this study is to investigate the possibility that amlodipine can modulate eNOS interaction with Cav-1. Using cultured EC, we confirm that amlodipine potentiates vascular endothelial growth factor (VEGF)-induced NO release. eNOS trafficking to specialized plasma membrane microdomains, which is essential to eNOS signaling, is unaffected by amlodipine. However, glutathione s-transferase (GST) pulldown assays reveal that amlodipine can prevent binding of native, acylated eNOS complexes to the active domain of Cav-1 in a concentration-dependent fashion, suggesting that amlodipine has an antagonistic effect on the native eNOS/Cav-1 signaling complex. Moreover, experiments performed in a reconstituted cell line confirm that amlodipine's effect on NO release is highly selective for the eNOS/Cav-1 interaction. To our knowledge, these data are the first to demonstrate a direct effect of amlodipine on the eNOS/Cav-1 protein complex and support the concept of developing novel therapies specifically aimed at modulating the eNOS/Cav-1 interaction to improve endothelial function in cardiovascular diseases.
authors.affiliation: Providence Heart + Lung Institute at St. Paul's Hospital, The James Hogg Research Centre, University of British Columbia, Canada.
authors.forename: Arpeeta
authors.initials: A
authors.lastname: Sharma
authors.forename: Andy
authors.initials: A
authors.lastname: Trane
authors.forename: Carol
authors.initials: C
authors.lastname: Yu
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Jasmin
authors.forename: Pascal
authors.initials: P
authors.lastname: Bernatchez
mesh_terms: D017311:Amlodipine / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D019556:COS Cells; D002121:Calcium Channel Blockers / Q000494:pharmacology* / Q000627:therapeutic use; D002318:Cardiovascular Diseases / Q000188:drug therapy; D002417:Cattle; D051242:Caveolin 1 / Q000378:metabolism*; D002522:Chlorocebus aethiops; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D009569:Nitric Oxide / Q000096:biosynthesis / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects
chemical_list: D002121:Calcium Channel Blockers; D051242:Caveolin 1; D017311:Amlodipine; D009569:Nitric Oxide; D052250:Nitric Oxide Synthase Type III