Figure 2.

PGE₂-stimulated NF-κB responsive luciferase reporter gene activity (A) and time course of phosphorylation of I-κBα (B) in HEK cells stably transfected with the human EP₁ receptor (HEK-EP1). (A) HEK-EP1 cells or HEK cells stably transfected with empty vector (HEK-pCEP4) were transiently transfected with an NF-κB luciferase reporter plasmid as described in the methods section and ∼18 h later, were treated either vehicle (veh) or 1 µM PGE₂ at 37°C. Luciferase activity was determined the next day. Data are the means ± SEM of triplicate measurements from a representative experiment that was repeated three times. ***P < 0.001 compared with the corresponding vehicle treatment; one-way anova, followed by Bonferroni post-test. (B) HEK-EP1 cells were treated with 1 µM PGE₂ for the indicated times at 37°C and lysates were prepared and subjected to immunoblot analysis with antibodies against either phospho-I-κBα (p-I-κBα) or vinculin. A representative immunoblot is shown from one of three independent experiments.