Functional signatures of the EP3 receptor. (A) FLIPR assay revealing dose-dependent calcium fluxes by hMCs stimulated with the indicated concentrations of PGE2, PGD2, or LTD4. Each tracing is representative of triplicate samples, all of which showed virtually identical responses. (B) Effect of overnight treatment with PTX on calcium flux by Fura-2-am-loaded hMCs stimulated with PGE2 (10 μM). Data are from 1 of 3 experiments in which a calcium response was elicited. (C) SDS-PAGE immunoblot showing signals corresponding to phosphorylated and total ERK MAPK in samples of hMCs stimulated for 5 minutes with the indicated agonists (1 μM each) in the presence or absence (-) of the MEK inhibitor, UO126, or PTX. Data are from a single experiment representative of 4 performed, all of which yielded similar results.
