Figure 1: Gefitinib dose response in human HK2 cells showing inhibition of pioglitazone- (Piog-) induced NHE3 (a) and AQP1 (b) in the presence of 0.1–1 μM of gefitinib. HK2 cells were studied for 48 hrs. Western blot was determined as described in Section 2. Representative images for NHE3, AQP1, and actin bands are shown. Normalized results are expressed as mean ± SEM; . * versus control.