Suppression of GRP78 with siRNA inhibited autophagy activation and neuroprotection induced by IPC in PC12 cells. (A) GRP78 siRNA1 cancelled the IPC-induced neuroprotection. Cells were transfected with GRP78 siRNA1 (40 nM) or negative control sequence (NC) twenty-four hours before the onset of IPC. Twelve hours after IPC, the cells were subjected to OGD for 10 h and cell viability was examined with CCK-8 kit. (B)-(D) The cells were harvested 12 h after IPC and subjected to Western blot analysis. (B) GRP78 siRNA1 reversed IPC-induced upregulation of GRP78. (C) GRP78 siRNA1 reversed IPC-induced upregulation of LC3II/LC3I. (D) GRP78 siRNA1 reversed IPC-induced upregulation of Beclin1. Bar represents mean ± SD, n = 3. *P < 0.05, **P < 0.01, ***P < 0.001 compared with the control group; $$P < 0.01 compared with the OGD group; %% P < 0.01 compared with the NC + IPC + OGD group; # P < 0.05 compared with the NC + IPC group.