Evaluation of β-AR/cAMP/PKA signaling pathway by RT-PCR. The NE-dependent stimulation of VEGF (A), IL-8 (B), and IL-6 (C) mRNA levels with a peak at 2 hours was observed in treatment of A549 cells with 10 μM NE (A, B, and C). This effect could not be blocked by phentolamine (PHEN) (D). Representative results of VEGF (E), IL-8 (F), and IL-6 (G) mRNA levels treated with NE, isoproterenol (ISO), dobutamine (DOB), terbutaline (TER), 8-CPT, forskolin (FOR), NE + H89 or NE + PKI for 2 hours. Values are presented as percent of untreated control levels. Each bar represents the mean ± SD. ND, not detectable. *, P ≤ 0.05; **, P ≤ 0.001.