Fig. 4.

Gefitinib increased the degree of H₂O₂-induced injury and decreased the recovery rate in MDCK cells. Control and Sec10-overexpressing MDCK cells were grown on Transwell filters in triplicate until transepithelial resistance (TER) levels reached steady state. All the filters were treated with 1 mM H₂O₂ for 30 min, with half the filters incubated with either 1 μM gefitinib or vehicle for 1 h before H₂O₂ treatment and 7 h afterward. A: TER was measured at the indicated time points. Time 0 represents the first measurement following the H₂O₂ treatment. *Point in time where the TER was significantly recovered from the nadir (#) experienced during H₂O₂ treatment. B: rate of TER recovery after the nadir (#) was calculated by linear regression analysis and testing of slopes using SPSS statistical software. Values are means ± SE of 3 separate experiments.