Fig. 5. TRPV4 regulates cochlear hair cell development by targeting MAPK signaling pathways. After pretreatment with the TRPV4 agonist GSK1016790A (GSK) or a combination of GSK1016790A and the p38 inhibitor SB203580 (GSK+SB), the effect of TRPV4 on cell proliferation of HEI-OC1 cells was detected using the MTT assay, and the effect of TRPV4 on cell apoptosis of HEI-OC1 cells was detected using the cell death detection ELISA-Plus apoptosis assay. (A) Inhibition of MAPK signaling rescued cell proliferation induced by TRPV4 in HEI-OC1 cells. (B) Disruption of MAPK signaling promoted cell apoptosis induced by TRPV4 in HEI-OC1 cells. Data are represented as means±SD from three independent experiments. ^*Indicates differences from euglycemic controls at p<0.05, ^†Indicates differences from euglycemic controls at p<0.01, ^‡Indicates differences from untreated controls at p<0.05, respectively. TRPV4, transient receptor potential vanilloid sub type 4; MSPK, mitogenactivated protein kinase.