Activation of CRE in PLB cells. PLB cells were transiently transfected with pGL3-ΔFcγRIIA-Luc reporter plasmid or pGL3-Luc as described in “Materials and methods,” and treated for 16 hours with 10 mM dbcAMP in the absence or presence of 10 μM H-89. Reporter activity is expressed as fold increase in luciferase activity, which was standardized to Renilla luciferase expression used as an internal control. Relative luciferase units ± SE (bars) of 3 independent experiments, each done in triplicate.