Oxidative stress caused by activation of NADPH oxidase 4 promotes contrast-induced acute kidney injury
HK-2 cells were incubated with iohexol for the indicated times (0 min, 5 min, 30 min, 1 h, 2 h, or 3 h). For examination of the long-term viability of HK-2 cells after iohexol exposure, the medium containing iohexol was removed after 5 min, 0.5 h, 1 h, 2 h, or 3 h and then replaced with fresh serum-free medium for 24 h, 23.5 h, 23 h, 22 h, or 21 h (5 min/24 h, 0.5/23.5 h, 1/23 h, 2/22 h or 3/21 h). (A) Effects of Nox4 on phosphorylation of MAPK family members (p38, JNK, and ERK), bax, bcl-2, and p65. (B and C) Effects of Nox4 knockdown and GKT137831 pretreatment on iohexol-induced apoptosis.