Fig. 4.

Effect of GPCR agonists, antagonists, and PDE inhibition on PKA activities. The Rluc-PCA was detected from transiently transfected HEK293T cells grown on white-walled 96-well microtiter plates. (A) Effect of combinations of alprenolol (10 μM, 60 min) pretreatment and isoproterenol (10 μM, 15 min) treatment of stable HEK293 clones expressing the β₂AR on Reg-F(1):Cat-F(2) or Reg-F(1):Reg-F(2) (mean ± SD from triplicates). (B) Effect of SR121463B (10 μM, 60 min) pretreatment and AVP (100 nM, 15 min) treatment of stable HEK293 clones expressing the V₂R on Reg-F(1):Cat-F(2) or Reg-F(1):Reg-F(2) (mean ± SD triplicates). (C) Stable V₂R-HEK293 and β₂AR-HEK293 cells were pretreated for indicated times with milrinone (10 μM) and increasing concentrations of rolipram (μM) followed by plate reader analysis of the effect on the Reg-F(1):Cat-F(2) (mean ± SD from three independent experiments). (D) Stable β₂AR-HEK293 cells were pretreated for 30 min with the selective β₂AR-antagonist ICI118,551 (1 μM) and isoproterenol (1 μM, 15 min) or increasing concentrations of rolipram (μM, 15 min) followed by Rluc-PCA analysis of Reg-F(1):Cat-F(2) (mean ± SD from three independent experiments).