On the functional significance of primate retinal dopamine receptors

Diverse dopamine receptors have been identified in the primate retina. Evidence summarized from human and monkey retinal electrophysiological studies (ERG) suggests that separate D1 and D2 receptor activation results in stimulus dependent antagonistic effects. Studies were performed using Haloperidol, l-sulpiride, CY 208-243 and dopamine. It is inferred that the antagonistic functions of D1 and D2 receptors synergistically determine the inverted U-shaped spatial contrast response function of the primate retina. An understanding of the logic performed by retinal D1 and D2 receptors may be useful to discern properties of the role of diverse dopamine receptors in basal ganglia DA circuits.