D2-dopamine receptor blockade impairs motion detection in goldfish.
Under photopic illumination conditions, motion detection in goldfish is dominated by the long-wavelength-sensitive cone type (L-cone), and under scotopic conditions motion it is determined by rods (Schaerer & Neumeyer, 1996). The switch from rod-dominated to cone-dominated motion detection occurs during light adaptation. It has been suggested that dopamine acts as a neuronal light-adaptative signal. It is known that dopamine affects wavelength discrimination through D1-dopamine receptors (Mora-Ferrer & Neumeyer, 1996), and the dorsal light reflex through D1- and D2-dopamine receptors (Lin & Yazulla, 1994a). The purpose of this study was to determine whether dopamine influenced movement detection by goldfish, and if so, which dopamine receptor was involved. The D2-dopamine receptor antagonist sulpiride reduced the animal's sensitivity to the moving stimulus, whereas SCH 23390, a D1-dopamine receptor antagonist, did not have any effect. The effect of sulpiride is discussed in relation to known sulpiride effects on retinal neurons and the retinal pigment epithelium.
Mora-Ferrer
C
C
Institut für Zoologie III. J. Gutenberg-Universität, Mainz, Germany. Carlos.Mora-ferrer@uni-mainz.de
Gangluff
V
V
D000221:Adaptation, Ocular; D000818:Animals; D001522:Behavior, Animal; D001552:Benzazepines / Q000494:pharmacology; D004298:Dopamine / Q000502:physiology*; D018492:Dopamine Antagonists / Q000494:pharmacology; D065127:Dopamine D2 Receptor Antagonists; D006054:Goldfish / Q000502:physiology*; D009039:Motion Perception / Q000502:physiology*; D010468:Perceptual Disorders / Q000503:physiopathology*; D020419:Photoreceptor Cells, Vertebrate / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors; D013469:Sulpiride / Q000494:pharmacology
D001552:Benzazepines; D018492:Dopamine Antagonists; D065127:Dopamine D2 Receptor Antagonists; D017447:Receptors, Dopamine D1; D013469:Sulpiride; D004298:Dopamine