Release of endogenous dopamine from the superfused rabbit retina in vitro: effect of light stimulation.
Light exposure activates dopamine (DA)-releasing neurons in the retina. Previous studies have employed indirect means (i.e. accumulation of DA metabolites in vivo4.11, or [3H]DA release from preloaded retina in vitro2) to estimate light-stimulated retinal DA release. We describe a new technique, based on superfusion of retinal pieces in vitro, which allows direct measurement of endogenous DA release. Dark-adapted pieces of retina from male albino rabbits were individually superfused in vitro with a physiologic buffer containing nomifensine (30 microM) (a DA reuptake blocker), and exposed to steady white light (300 microW/cm2) for 15 min. Retinal DA release into the superfusate was significantly greater (60%) during photic stimulation than during dark-exposure.
Godley
B F
BF
Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge 02139.
Wurtman
R J
RJ
D000818:Animals; D004298:Dopamine / Q000378:metabolism* / Q000502:physiology; D066298:In Vitro Techniques; D008029:Lighting; D008297:Male; D009627:Nomifensine / Q000494:pharmacology; D010775:Photic Stimulation; D011188:Potassium / Q000494:pharmacology; D011817:Rabbits; D012160:Retina / Q000378:metabolism* / Q000502:physiology; D013997:Time Factors
D009627:Nomifensine; D011188:Potassium; D004298:Dopamine