Figure 4. Immunochemistry of a normal monkey eye. Sections from normal retina and iris were examined by immunohistochemistry with anti-vascular endothelial growth factor (VEGF) antibody and anti-apelin antibody. A: Positive staining (brown) of VEGF was showed in the retinal vessel walls. B: Positive staining (brown) of apelin was showed in the retinal vessel walls. C: There was no positive staining of VEGF in the section of iris. D: There was no positive staining of apelin in the section of iris.