Ethanol Inhibition of N‐Methyl‐D‐Aspartate‐Stimulated Endogenous Dopamine Release from Rat Striatal Slices: Reversal by Glycine

N‐Methyl‐D‐aspartate stimulated a concentration‐dependent release of endogeneous dopamine from rat striatal slices. The threshold for activation was between 10 and 25 μM and reached a maximum at 1 mM. Release was completely blocked by magnesium or tetrodotoxin. Ethanol (10–200 mM) significantly inhibited the N‐methyl‐D‐aspartate‐stimulated release of dopamine by 20–45%, with half‐maximal inhibition occurring at ∼21 mM. Addition of ethanol plus increasing concentrations of magnesium resulted in a greater inhibition of N‐methyl‐D‐aspartate‐stimulated dopamine release than that observed with magnesium alone. However, this effect appeared to be due to a noninteractive additive effect of the two antagonists, as the IC50 value for magnesium inhibition was not significantly altered by ethanol. Glycine, which had no effect on dopamine release by itself, completely reversed the inhibitory effects of ethanol (25 mM) at low micromolar concentrations. These results suggest that ethanol may produce its effects in striatal slices by interfering with a glycine modulatory site of the N‐methyl‐D‐aspartate receptor‐ionophore complex.

[1]  R. Forney,et al.  Aliphatic alcohols. , 1967, Progress in chemical toxicology.

[2]  T. Chou,et al.  Derivation and properties of Michaelis-Menten type and Hill type equations for reference ligands. , 1976, Journal of theoretical biology.

[3]  R. Harris,et al.  Inhibition of synaptosomal calcium uptake by ethanol. , 1980, The Journal of pharmacology and experimental therapeutics.

[4]  R. H. Evans,et al.  Excitatory amino acid transmitters. , 1981, Annual review of pharmacology and toxicology.

[5]  R. Farrar,et al.  Inhibition of fast- and slow-phase depolarization-dependent synaptosomal calcium uptake by ethanol. , 1983, The Journal of pharmacology and experimental therapeutics.

[6]  M. Mayer,et al.  Voltage-dependent block by Mg2+ of NMDA responses in spinal cord neurones , 1984, Nature.

[7]  J. Woodward,et al.  Correlation of rates of calcium entry and endogenous dopamine release in mouse striatal synaptosomes , 1985, Brain Research.

[8]  W. A. Hunt Alcohol and biological membranes , 1985 .

[9]  R. Farrar,et al.  Chronic ethanol treatment uncouples striatal calcium entry and endogenous dopamine release , 1986, Brain Research.

[10]  S. W. Leslie,et al.  Inhibition of fast phase calcium uptake and endogenous norepinephrine release in rat brain region synaptosomes by ethanol , 1986, Brain Research.

[11]  J. Woodward,et al.  Characterization of dihydropyridine-sensitive calcium channels in rat brain synaptosomes. , 1988, Proceedings of the National Academy of Sciences of the United States of America.

[12]  G. Westbrook,et al.  Modulation of excitatory synaptic transmission by glycine and zinc in cultures of mouse hippocampal neurons , 1988, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[13]  R. Ransom,et al.  NMDA-induced hippocampal [3H]norepinephrine release is modulated by glycine. , 1988, European journal of pharmacology.

[14]  C. Cotman,et al.  Two classes of N-methyl-D-aspartate recognition sites: differential distribution and differential regulation by glycine. , 1988, Proceedings of the National Academy of Sciences of the United States of America.

[15]  R. Miller,et al.  Multiple sites for the regulation of the N-methyl-D-aspartate receptor. , 1988, Molecular pharmacology.

[16]  M. Jarvis,et al.  The N-methyl-D-aspartate receptor complex. , 1988, Journal of receptor research.

[17]  A. Thomson Glycine modulation of the NMDA receptor/channel complex , 1989, Trends in Neurosciences.

[18]  R. Ransom,et al.  Glycine modulation of NMDA-evoked release of [3H]acetylcholine and [3H]dopamine from rat striatal slices , 1989, Neuroscience Letters.

[19]  S. W. Leslie,et al.  Ethanol inhibits NMDA-induced increases in free intracellular Ca2+ in dissociated brain cells , 1989, Brain Research.

[20]  K. Jhamandas,et al.  Characterization of L-glutamate action on the release of endogenous dopamine from the rat caudate-putamen. , 1989, The Journal of pharmacology and experimental therapeutics.

[21]  R. Araneda,et al.  Modulation of Dendritic Release of Dopamine by N‐Methyl‐D‐Aspartate Receptors in Rat Substantia Nigra , 1989, Journal of neurochemistry.

[22]  R. Watson Biochemistry and physiology of substance abuse , 1989 .

[23]  G White,et al.  Ethanol inhibits NMDA-activated ion current in hippocampal neurons. , 1989, Science.

[24]  R. Compton,et al.  Characterization df a [3H]Glycine Recognition Site as a Modulatory Site of the N‐Methyl‐D‐Aspartate Receptor Complex , 1989, Journal of neurochemistry.

[25]  B. Tabakoff,et al.  N‐Methyl‐D‐Aspartate Receptors and Ethanol: Inhibition of Calcium Flux and Cyclic GMP Production , 1989, Journal of neurochemistry.

[26]  G. Lynch,et al.  A Glycine Site Associated with N‐Methyl‐d‐Aspartic Acid Receptors: Characterization and Identification of a New Class of Antagonists , 1989, Journal of neurochemistry.