BAPTA inhibited autophagy activation and neuroprotection induced by IPC in primary cultured cortical neurons. (A) Cortical neurons were exposed to OGD for 30 min to induce IPC. Twenty-four hours after IPC, the neurons were subjected OGD for 4 h. The cell viability was examined with CCK8. (B), (C) The cells were harvested 0, 6, 12 and 24 h after IPC. (B) GRP78 was upregulated after IPC. (C) LC3II/LC3I was upregulated after IPC. (D), (E) The neurons were incubated with BAPTA 60 min before the onset of IPC and harvested 12 h after IPC. (D) BAPTA reduced IPC-induced upregulation of GRP78. (E) BAPTA reduced IPC-induced upregulation of LC3II/LC3I. 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 < 0.05 compared with the IPC + OGD group; # P < 0.05 compared with the IPC group. B (L) = BAPTA 0.125 μM; B (M) = BAPTA 0.5 μM; B (H) = BAPTA 2 μM.