Figure 8.

Co-localization of the α₂ and β₂ subunits in adult human eye. (A) A phase-contrast image of the human eye section studied. The RPE layer and the choroid are indicated. This section was co-stained for the β₂ (B) and α₂ subunits (C) of Na⁺, K⁺-ATPase using Alexa 488- and Alexa 594-conjugated donkey anti-rabbit and anti-mouse IgG secondary antibodies, respectively. The merged image showing co-localization at the apical domain is in (D). Panels (E,F) show images of similar sections treated only with the secondary fluorescent antibody (anti-rabbit and anti-mouse, IgG, respectively) as a negative control. Panel (G) shows the field indicated by the square in (D) at higher magnification. All the preparations were counterstained with DAPI (blue). Arrows indicate the apical domain of RPE cells. Scale bars are 25 μm in (A–D), 40 μm in (E,F) and 30 μm in (G).