Fig. 4.

β-Arrestin is not recruited to FP receptor in response to either PGF2α or AL-8810. A, Images obtained by confocal microscopy showing redistribution of β-arrestin-2-YFP after 1 μm PGF2α, 10 μm AL-8810 in FP-R cells, or 1 μm AngII treatment in HA-AT1R cells. B, FP-R cells or AT1R cells were serum starved for 1 h before stimulation with 1 μm AngII, 1 μm PGF2α, or 10 μm AL8810 at indicated time points. HA-tagged receptors were immunoprecipitated, and cell lysates were Western blotted using anti-β-arrestin (clone 3978, see Materials and Methods), antiphospho ERK1/2, or anti-HA antibodies (IP indicates immunoprecipitation). Results are representative of three independent experiments. NT, Not treated; WB, Western blot.