Fig 5.

Antioxidants blocked Ang II-induced Src activation and prolonged EGFR-ERK signaling in AT1R/Cl4 cells. (A and B) Nox4 siRNA- or scrambled control siRNA-transfected AT1R/Cl4 cells were treated as indicated, and the cell lysates were subjected to immunoblotting with indicated antibodies (A) or cell photographs were taken at ×400 magnification after FITC-conjugated phalloidin staining (B). (C) ROS production was measured by the fluorescence intensity of 2′,7′-dichlorodihydrofluorescin (DCFH) in Ang II-treated AT1R/Cl4 cells with or without a NADPH oxidase inhibitor, apocynin pretreatment. (D and E) AT1R/Cl4 cell lysates were immunoblotted with indicated antibodies after the cells were exposed to indicated stimuli following pretreatment with or without an antioxidant, N-acetylcysteine (NAC; 5 mM) (D) or tempol (3 mM) (E).