Effect of Intracerebral Administration of NMDA and AMPA on Dopamine and Glutamate Release in the Ventral Pallidum and on Motor Behavior

• Published in: Journal of neurochemistry Vol. 74; no. 5; pp. 2049 - 2057
• Main Authors: Kretschmer, Beate D., Goiny, Michel, Herrera‐Marschitz, Mario
• Format: Journal Article
• Language: English
• Published: Oxford UK Blackwell Science Ltd 01.05.2000; Blackwell
• Subjects: alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid - administration & dosage; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid - pharmacology; Animals; Basal ganglia; Behavior, Animal - drug effects; Biological and medical sciences; Brain - physiology; Central nervous system; Central neurotransmission. Neuromudulation. Pathways and receptors; Dopamine; Dopamine - metabolism; Excitatory Amino Acid Agonists - administration & dosage; Excitatory Amino Acid Agonists - pharmacology; Fundamental and applied biological sciences. Psychology; Globus Pallidus - metabolism; Glutamate; Glutamic Acid - metabolism; Injections; Locomotion; Male; Medicin och hälsovetenskap; Microdialysis; Motor Activity - drug effects; N-Methylaspartate - administration & dosage; N-Methylaspartate - pharmacology; Rats; Rats, Sprague-Dawley; Tegmentum Mesencephali - drug effects; Tegmentum Mesencephali - physiology; Ventral pallidum; Ventral tegmental area; Vertebrates: nervous system and sense organs; Rat; Rodentia; Central nervous system; Basal ganglion; Glutamate receptor; Glutamate; Pallidum; Locomotion; Dopaminergic transmission; Vertebrata; AMPA receptor; Mammalia; Animal activity; Intracerebral administration; Excitatory aminoacid; Neurotransmitter; NMDA receptor; Release; Brain (vertebrata)
• ISSN: 0022-3042; 1471-4159
• DOI: 10.1046/j.1471-4159.2000.0742049.x

: The present study investigates the modulation of the ventral tegmental area (VTA)‐ventral pallidum (VP) dopaminergic system by glutamate agonists in rats. The glutamate receptor agonists N‐methyl‐D‐aspartate (NMDA) and α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole‐propionic acid (AMPA) were infused via reversed microdialysis into the VTA, and dopamine (DA), glutamate, and aspartate levels in the VTA and ipsilateral VP were monitored together with motor behavior screened in an open field. NMDA (750 μM) infusion, as well as AMPA (50 μM) infusion, induced an increase of DA and glutamate levels in the VTA, followed by an increase of DA levels in the ipsilateral VP and by enhanced locomotor activity. The increase of DA in the VP was similar after administration of these two glutamate agonists, although motor activity was more pronounced and showed an earlier onset after NMDA infusion. Glutamate levels in the VP were not increased by the stimulation of DA release. It is concluded that DA is released from mesencephalic DA neurons projecting to the VP and that these neurons are controlled by glutamatergic systems, via NMDA and AMPA receptors. Thus, DA in the VP has to be considered as a substantial modulator. Dysregulation of the mesopallidal DA neurons, as well as their glutamatergic control, may play an additional or distinct role in disorders like schizophrenia and drug addiction.