?Real time? measurement of endogenous dopamine release during short trains of pulses in slices of rat neostriatum and nucleus accumbens : role of autoinhibition

1991 ◽  
Vol 344 (6) ◽  
Author(s):  
Norbert Limberger ◽  
StephenJ. Trout ◽  
ZygmuntL. Kruk ◽  
Klaus Starke
Keyword(s):  
Nucleus Accumbens ◽  
Real Time ◽  
Dopamine Release ◽  
Time Measurement ◽  
Endogenous Dopamine ◽  
Real Time Measurement ◽  
Endogenous Dopamine Release

Regulation of endogenous dopamine release in amphibian retina by gamma-aminobutyric acid and glycine

1994 ◽  
Vol 11 (5) ◽  
pp. 1003-1012 ◽  
Author(s):  
Jeffrey H. Boatright ◽  
Nara M. Rubim ◽  
P. Michael Iuvone
Keyword(s):  
Receptor Agonist ◽  
Dopamine Release ◽  
Receptor Activation ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Gaba A ◽  
Endogenous Dopamine ◽  
Endogenous Dopamine Release ◽  
Inhibitory Tone

AbstractEndogenous dopamine release in the retina of the African clawed frog (Xenopus laevis) increases in light and decreases in darkness. The roles of the inhibitory amino acid transmitters gamma-aminobutyric acid (GABA) and glycine in regulating this light/dark difference in dopamine release were explored in the present study. Exogenous GABA, the GABA-A receptor agonist muscimol, the GABA-B receptor agonist baclofen, and the GABA-C receptor agonist cis-aminocrotonic acid (CACA) suppressed light-evoked dopamine overflow from eyecups. The effects of GABA-A and -B receptor agonists were selectively reversed by their respective receptor-specific antagonists, whereas the effect of CACA was reversed by the competitive GABA-A receptor antagonist bicuculline. The benzodiazepine diazepam enhanced the effect of muscimol on light-evoked dopamine release. Both GABA-A and -B receptor antagonists stimulated dopamine release in light or darkness. Bicuculline was more potent in light than in darkness. These data suggest that retinal dopaminergic neurons are inhibited by GABA-A and -B receptor activation in both light and darkness but that GABA-mediated inhibitory tone may be greater in darkness than in light.Exogenous glycine inhibited light-stimulated dopamine release in a concentration-dependent and strychnine-sensitive manner. However, strychnine alone did not increase dopamine release in light or darkness, nor did it augment bicuculline-stimulated release in darkness. Additionally, both strychnine and 7-chlorokynurenate, an antagonist of the strychnine-insensitive glycine-binding site of the N-methyl-D-aspartate subtype of glutamate receptor, suppressed light-evoked dopamine release. Thus, the role of endogenous glycine in the regulation of dopamine release remains unclear.

scholarly journals Biphasic inhibition of stimulated endogenous dopamine release by 7-OH-DPAT in slices of rat nucleus accumbens

1995 ◽  
Vol 115 (3) ◽  
pp. 421-426 ◽  
Author(s):  
Jyoti Patel ◽  
Stephen J. Trout ◽  
Peter Palij ◽  
Robin Whelpton ◽  
Zygmunt L. Kruk
Keyword(s):  
Nucleus Accumbens ◽  
Dopamine Release ◽  
Endogenous Dopamine ◽  
Endogenous Dopamine Release ◽  
Rat Nucleus Accumbens

Real-time measurement of dopamine release in rat brain

1986 ◽  
Vol 381 (1) ◽  
pp. 168-171 ◽  
Author(s):  
Werner G. Kuhr ◽  
R. Mark Wightman
Keyword(s):  
Rat Brain ◽  
Real Time ◽  
Dopamine Release ◽  
Time Measurement ◽  
Real Time Measurement

Regulation of endogenous dopamine release in amphibian retina by melatonin: The role of GABA

1994 ◽  
Vol 11 (5) ◽  
pp. 1013-1018 ◽  
Author(s):  
Jeffrey H. Boatright ◽  
Nara M. Rubim ◽  
P. Michael Iuvone
Keyword(s):  
Dopamine Release ◽  
Rank Order ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Gaba A ◽  
Endogenous Dopamine ◽  
Frog Retina ◽  
Endogenous Dopamine Release ◽  
Clawed Frog

AbstractIn the retina of the African clawed frog (Xenopus laevis), endogenous dopamine release increases in light and decreases in darkness. Exogenous melatonin and several chemical analogs of melatonin suppressed light-evoked dopamine release from frog retina in a concentration-dependent manner. The rank order of potency for inhibition of light-evoked dopamine release was melatonin » 5-methoxytryptamine ≥ N-acetylserotonin > 5-methoxytryptophol ⋙ serotonin. Melatonin did not suppress dopamine release below levels seen in darkness. The putative melatonin receptor antagonist luzindole inhibited the effect of melatonin. Luzindole enhanced dopamine release in darkness but had little effect in light. These data suggest a role for endogenous melatonin in dark-induced suppression of retinal dopamine.Picrotoxin and bicuculline, GABA-A receptor antagonists, blocked melatonin-induced suppression of dopamine release. In the presence of melatonin, bicuculline was significantly less potent in stimulating dopamine release. These results suggest that melatonin enhances GABAergic inhibition of light-evoked dopamine release. This mechanism may underlie the light/dark difference in dopamine release in vertebrate retina.

Sign in / Sign up

Export Citation Format

Share Document