Figure 7.

D₁ receptors colocalized with the ON dendrites of A8 cell and most but not all AII cells. (A) Maximum projection of the inner dendrites of a dye-injected A8 cell. (B) Overlay of the A8 ON dendrites and D₁ receptors (D1R), shown as maximum projection. (C,D) Selected ROI from B. (C'–D”') Magnified images of A8 dendrites (C',D'), D₁ receptors (C”,D”), and their respective overlay (C”',D”') within a single section from the selected ROI. Arrows denote colocalization of D₁ receptors with A8 ON dendrites. (E–H”') Same as (A–D”') for an injected AII cell. Arrows point to D₁ receptor immunoreactivity colocalizing with AII dendrites. (I–L”') Same as (E–H”'), however, this AII cell did not show colocalization with D₁ receptor staining (arrowheads), consistent with a previous report on the rat retina (Veruki and Wässle, 1996). Scale bar: (A,B,E,F,I,J), 10 μm; (C'–D”'), (G'–H”'), (K'–L”'), 2 μm.