Figure 2.

D1a-receptor-like immunoreactivity in ganglion cells in vertical sections. Ganglion cells identified by retrograde transport of Alexa Fluor 488-coupled dextran introduced into the optic nerve. Labeling with anti-D1a-receptor antibody visualized with Alexa Fluor 555-conjugated secondary antibody. Images are single confocal optical sections obtained with a 40x oil immersion objective. Fluorescence due to each dye obtained individually. A, Direct overlay of fluorescent signals from retrogradely-transported dextran (backfill, in green) and anti-D1a-receptor antibody (D1a, in red) indicate ganglion cells exhibiting D1a-receptor-like immunoreactivity (orange-yellow). Labels along right side indicate position of outer nuclear layer (onl), inner nuclear layer (inl), inner plexiform layer (ipl), and ganglion cell layer (gcl). B, Example of same labeling from a different retina. Immunopositive dendrites emerge from a large soma in right-hand half of panel, and project into distal half of ipl. C, Images of a section obtained under the exact same conditions as B, except that the anti-D1a-receptor antibody was pre-incubated with immunogen before application to section. Scale bar (25 μm) applies to all panels.