Fig. 3.

Silencing of PDE4B ameliorates OGD-triggered ER stress in HT-22 cells. (A, C, E) HT-22 cells were transfected with negative control si-RNA (NC) or si-RNA for PDE4B (si-PDE4B). At 18–24 h after transfection, the cells were subjected to 6 h of OGD. The protein levels of GRP78, p-eIF2α, eIF2α, and CHOP were determined by Western blotting. (B, D, F) The relative levels of GRP78/β-tubulin (n = 4), p-eIF2α/eIF2α (n = 5) and CHOP/β-tubulin (n = 4) were measured by semiquantitative analysis of the Western blots. (G) HT-22 cells transfected with NC or si-PDE4B were subjected to OGD for 6 h and re-oxygenation for 24 h, and then the cell viability was detected by a CCK-8 assay. (12 duplications from three independent experiment, n = 3). (H, I) HT-22 cells were processed as described above, and the protein levels of cleaved-caspase 3 were determined by Western blotting. The relative level of cleaved-caspase 3/pro-caspase 3 was measured by semiquantitative analysis of the blots (n = 4). Results are expressed as the mean ± SD, *P < 0.05, **P < 0.01 versus the indicated group.