Immunoreactivity for VEGF in the spiral ganglion cells. Little or no staining was detected in the spiral ganglion cells of the untreated samples (A; Normal). VEGF expression (green) was weakly detected in a few spiral ganglion neurons in samples treated with physiological saline (B; Saline) and those treated with 0.1% DMSO (D; DMSO). VEGF expression was strongly detected in a large number of the spiral ganglion neurons treated with EP2 agonist (C; EP2 agonist) or EP4 agonist (E; EP4 agonist). Nuclei were labeled with DAPI. The specimens were viewed with 63× oil objective. Scale bar = 200 μm.