N-Methyl-D-aspartate receptors and release of newly-synthesized [3H]dopamine in nucleus accumbens slices and its relationship with neocortical afferences.
1. The effects of excitatory amino acid agonists on the release of newly-synthesized [3H]dopamine was examined in slices of nucleus accumbens of the rat. 2. L-glutamate and N-methyl-D-aspartate stimulated the release of newly-synthesized [3H]dopamine, which was completely inhibited by physiological concentrations of magnesium and by the selective and non-competitive antagonist MK-801. 3. Other ligands for excitatory amino acids subtype receptors, such as AMPA and kainic acid, had no effect of newly-synthesized [3H]dopamine release. 4. Frontal cortical ablation produced a significant increase on the N-methyl-D-aspartate-stimulated release of [3H]dopamine. 5. These data suggest that dopaminergic function in the rat nucleus accumbens is modulated by N-methyl-D-aspartate receptors, the sensitivity of which is determined, at least in part, by glutamatergic and/or aspartergic afferents from the frontal cortex.
Asencio
H
H
Laboratory of Biochemical Pharmacology, Catholic University of Chile, Santiago.
Bustos
G
G
Gysling
K
K
Labarca
R
R
D000200:Action Potentials / Q000502:physiology; D000344:Afferent Pathways / Q000502:physiology; D000596:Amino Acids / Q000502:physiology; D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D016291:Dizocilpine Maleate / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D016202:N-Methylaspartate / Q000378:metabolism; D009714:Nucleus Accumbens / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D016194:Receptors, N-Methyl-D-Aspartate / Q000502:physiology*
D000596:Amino Acids; D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D011188:Potassium; D004298:Dopamine