Release pattern of endogenous dopamine in teleost retinae during light adaptation and pharmacological stimulation.
The release of endogenous dopamine from teleost retinae was studied using high-performance-liquid-chromatography and electrochemical detection. Dopamine was measured in superfusates of isolated retinae after stimulation with flickering light as well as in the presence of GABA, L-glutamate, kainate or taurine. The effect of the receptor antagonists bicuculline, picrotoxin and kynurenic acid was also tested in retinae kept in the dark. We report a low level, basal release of dopamine in the dark (20 pg x 10 min-1/retina), which is transiently increased by stimulation with flickering light. This light evoked release of dopamine is inhibited by GABA and L-glutamate, whilst antagonists of these retinal transmitters stimulate release in the dark.
Kirsch
M
M
Institut für Anatomie und Zellbiologie der Universitaet Marburg, F.R.G.
Wagner
H J
HJ
D000221:Adaptation, Ocular; D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D002347:Carps / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003530:Cyprinidae / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D005971:Glutamates / Q000494:pharmacology; D007736:Kynurenic Acid / Q000494:pharmacology; D010775:Photic Stimulation; D010852:Picrotoxin / Q000494:pharmacology; D012160:Retina / Q000187:drug effects / Q000378:metabolism*; D013654:Taurine / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D001640:Bicuculline; D004298:Dopamine; D005971:Glutamates; D007736:Kynurenic Acid; D010852:Picrotoxin; D013654:Taurine; D005680:gamma-Aminobutyric Acid