Functional expression of PDE3 in HAECs.

<p>(A) Top, Representative immunoblot showing PDE3A and PDE3B expression in human adipose, artery, and HAECs. Bottom, Fluorescence microscopy analysis of PDE3A and PDE3B expression in HAECs (green, VE-Cadherin; red, PDE3A or 3B). (B) Top, Effect of PDE3-targeting siRNAs (iPDE3A and 3B) or non-targeting siRNAs (iCt) on protein levels in HAEC. Bottom, Down-regulation of PDE3A and PDE3B expression increases intracellular cAMP levels in HAECs. HAECs were transfected with a iCT, iPDE3A, or iPDE3B. Post-transfection HAECs were treated with vehicle (Veh) or 30 μM cilostazol (C30), and then the intracellular cAMP concentration was determined. (C) Down-regulation of PDE3A and PDE3B expression increases PGI<sub>2</sub> production in HAECs. HAECs were transfected with a iCT, iPDE3A, or iPDE3B. Post-transfection HAECs were treated with vehicle (Veh) or 30 μM cilostazol (C30), and then the PGI<sub>2</sub> concentration in medium was determined (n = 4; †† <i>p</i> < 0.01 vs. iCT, <i>t</i>-test; ** <i>p</i> < 0.01 vs. Veh, <i>t</i>-test).</p>