RTV elicited ICl,swell via ROS from mitochondria but not NADPH oxidase. (A, B) Apocynin (Apo; 500 μM, 20 min), a specific NADPH oxidase inhibitor, failed to suppress RTV (15 μM, 20 min)-induced ICl,swell (n = 4; Ctrl vs. RTV, P <0.001; RTV vs. +Apo, P = 0.98; Ctrl vs. +Apo, P <0.001). (C, D) In contrast, rotenone (Rot; 10 μM, 30 min), which suppresses mitochondrial ROS production, fully inhibited RTV-induced ICl,swell (n = 5; Ctrl vs. RTV, P <0.001; RTV vs. +Rot, P <0.001; Ctrl vs. +Rot, P = 0.89).