ADP-Induced Ca2+ Signaling and Proliferation of Rat Ventricular Myofibroblasts Depend on Phospholipase C-Linked TRP Channels Activation Within Lipid Rafts

作者：Certal, Mariana; Vinhas, Adriana; Barros-Barbosa, Aurora; Ferreirinha, Fatima; Costa, Maria Adelina; Correia-De-Sa, Paulo^*

来源：Journal of Cellular Physiology, 2017, 232(6): 1511-1526.

DOI：10.1002/jcp.25656

• HUMAN SUBCUTANEOUS FIBROBLASTS
• PLASMA-MEMBRANE MICRODOMAINS
• URIDINE TRIPHOSPHATE UTP
• CARDIAC FIBROBLASTS
• COLLAGEN-SYNTHESIS
• INOSITOL PHOSPHATES
• RECEPTOR ACTIVATION
• ATP RELEASE
• CELLS
• HEART

Nucleotides released during heart injury affect myocardium electrophysiology and remodeling through P2 purinoceptors activation in cardiac myofibroblasts. ATP and UTP endorse [Ca2+] i accumulation and growth of DDR-2/alpha-SMA-expressing myofibroblasts from adult rat ventricles via P2Y(4) and P2Y(2) receptors activation, respectively. Ventricular myofibroblasts also express ADP-sensitive P2Y(1), P2Y(12), and P2Y(13) receptors as demonstrated by immunofluorescence confocal microscopy and western blot analysis, but little information exists on ADP effects in these cells. ADP (0.003-3 mM) and its stable analogue, ADP beta S (100 mu M), caused fast [Ca2+] i transients originated from thapsigargin-sensitive internal stores, which partially declined to a plateau sustained by capacitative Ca2+ entry through transient receptor potential (TRP) channels inhibited by 2-APB (50 mu M) and flufenamic acid (100 mu M). Hydrophobic interactions between Gq/11-coupled P2Y purinoceptors and TRP channels were suggested by prevention of the ADP-induced [Ca2+] i plateau following PIP2 depletion with LiCl (10 mM) and cholesterol removal from lipid rafts with methyl-beta-cyclodextrin (2 mu M). ADP [Ca2+] i transients were insensitive to P2Y(1), P2Y(12), and P2Y(13) receptor antagonists, MRS2179 (10 mu M), AR-C66096 (0.1 mu M), and MRS2211 (10 mu M), respectively, but were attenuated by suramin and reactive blue-2 (100 mu M) which also blocked P2Y(4) receptors activation by UTP. Cardiac myofibroblasts growth and type I collagen production were favored upon activation of MRS2179-sensitive P2Y(1) receptors with ADP or ADP beta S (30 mu M). In conclusion, ADP exerts a dual role on ventricular myofibroblasts: [Ca2+] i transients are mediated by fast-desensitizing P2Y(4) receptors, whereas the profibrotic effect of ADP involves the P2Y(1) receptor activation. Data also show that ADP-induced capacitative Ca2+ influx depends on phospholipase C-linked TRP channels opening in lipid raft microdomains.

• 出版日期2017-6