Dopaminergic amacrine cells, although few in number, form a mosaic covering the entire retina.The release of dopamine is dependent on light intensity as well as the spatio-temporal properties of the light stimulus.The dopaminergic cells are, in part, driven by ON-bipolar cells, and are also under the control of reciprocal inhibitory interactions with photoreceptors (using the modulator melatonin) and another population of amacrine cells which uses enkephalins, neurotensin and somatostatin are transmitters.The rate of dopamine release is thus maintained at a low level in the dark, but increases with light intensity and spatio-temporal contrast in the light.Dopamine appears to be involved in a large range of functions, including regulation of light adaptation, and horizontal cell coupling.