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Modulation of dendritic release of dopamine by N-methyl-D-aspartate receptors in rat substantia nigra.
Modulation of dendritic release of dopamine by N-methyl-D-aspartate receptors in rat substantia nigra.
- Source :
-
Journal of neurochemistry [J Neurochem] 1989 Mar; Vol. 52 (3), pp. 962-70. - Publication Year :
- 1989
-
Abstract
- A superfusion system was used to study the effects of excitatory amino acids (EAA) on release of [3H]dopamine ([3H]DA) previously taken up by rat substantia nigra (SN) slices. The EAA tested (20-250 microM), with the exception of quisqualate and kainate, markedly evoked [3H]DA release from nigral slices when Mg2+ ions were omitted from the superfusion medium. The EAA receptor agonists exhibited the following relative potency in stimulating [3H]DA release: L-glutamate (L-Glu) greater than N-methyl-D-aspartate (NMDA) greater than NM(D,L)A greater than D-Glu much greater than quisqualate = kainate. D-2-Amino-5-phosphonovalerate (100-200 microM), an antagonist for NMDA receptors, substantially reduced [3H]DA release evoked by L-Glu or NMDA. In contrast, L-Glu diethyl ester (100-200 microM) produced a lesser blocking effect on [3H]DA release evoked by the EAA. Further experiments showed that the NMDA-mediated release of [3H]DA was totally suppressed by the omission of Ca2+ or by the addition of tetrodotoxin (0.1 microM) to the superfusion medium. In addition, strychnine, an antagonist for glycine (Gly) receptors, significantly decreased NMDA (100 microM)-evoked as well as glycine (100 microM)-evoked release of [3H]DA from nigral slices. The results shown support the idea that activation of NMDA subtype receptors in SN may trigger a Ca2+-dependent release of DA from dendrites of nigro-striatal DA-containing neurons. Furthermore, a transsynaptic mechanism that may partially involve Gly-containing interneurons is proposed to account for some of the events mediating NMDA receptor activation and DA release in SN.
- Subjects :
- Animals
Aspartic Acid analogs & derivatives
Aspartic Acid pharmacology
Calcium pharmacology
Dendrites drug effects
Glutamates pharmacology
Glutamic Acid
Glycine pharmacology
Kainic Acid pharmacology
Kinetics
Male
N-Methylaspartate
Oxadiazoles pharmacology
Quisqualic Acid
Rats
Rats, Inbred Strains
Receptors, N-Methyl-D-Aspartate
Substantia Nigra ultrastructure
Tetrodotoxin pharmacology
Amino Acids pharmacology
Dendrites physiology
Dopamine metabolism
Receptors, Neurotransmitter physiology
Substantia Nigra metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0022-3042
- Volume :
- 52
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- Journal of neurochemistry
- Publication Type :
- Academic Journal
- Accession number :
- 2563759
- Full Text :
- https://doi.org/10.1111/j.1471-4159.1989.tb02548.x