Fig. 1. The effect of EP₃ receptor stimulation on the localization of AQP2 in IMCD cells. IMCD cells were left untreated (control) or incubated with AVP (100 nM; 15 minutes), the EP₁/EP₃ receptor agonist sulprostone (1 µM; 30 minutes), or the EP₁ receptor antagonist SC19220 (10 µM; 40 minutes). If cells were incubated with both sulprostone and SC19220, the SC19220 (10 µM) was added 10 minutes prior to sulprostone (1 µM). AVP was present during the final 15 minutes. After completion of incubations, cells were fixed, permeabilized, and incubated with rabbit anti-AQP2 antibody and secondary Cy3-conjugated anti-rabbit antibodies. AQP2 immunofluorescence was detected by laser scanning microscopy. Scale bars: 20 µm.