Activities of JNK (p-JNK) detected by Western blot and immunofluorescence analysis in HUVECs transfected with or without si-CD31 and si-Neg before and after low shear stress treatment. (A) Western blot analysis of JNK expression (p-JNK and t-JNK) in HUVECs with different stimulations. (B) Representative immunofluorescence images showing p-JNK staining (green). DAPI blue staining of cell nuclei is shown. Bar = 20 µm. (C) Quantitation of JNK (p-JNK/t-JNK) in different groups by Western blot analysis. (D) Quantitation of relative p-JNK level (IOD) normalized to control of static group. *P < 0.05 versus static group. ▲P < 0.05 versus control of static group. ●P < 0.05 versus control of low shear stress group.