Figure 4.

GPR4 Activation by Acidosis Increases Cellular Permeability in HUVECs

(A and B) Quantitative analysis of cellular permeability in vitro. GPR4 activation by acidic pH increases cellular permeability using the FITC-dextran cellular permeability assay with HUVECs. Relative fold increase of cellular permeability in (A) HUVEC/vector, HUVEC/GPR4, and HUVEC/R115A cells and (B) HUVEC/control shRNA and HUVEC/GPR4 shRNA cells. Cells were treated for 5 h with either physiological pH 7.4 or acidic pH 6.4. All experiments were performed in duplicate and are representative of at least three experiments. Data are presented as mean ± SEM and analyzed for statistical significance using ANOVA where *p < 0.05, **p < 0.01, and ***p < 0.001.