Regulation of dopamine uptake in rat striatal tissue by NMDA receptors as measured using rotating disk electrode voltammetry.
Rotating disk electrode (RDE) voltammetry was used to examine the effect of N-methyl-D-aspartate (NMDA) on the initial velocity of dopamine (DA) uptake in suspensions of rat striatal tissue. Transport velocities were determined by measuring the rate of clearance of 2 microM DA added to the tissue suspension. NMDA (200 microM) was found to increase the initial velocity of DA transport from 548 +/- 28 to 803 +/- 63 pmol/s per g tissue (mean +/- SEM; P < 0.005). The increase was reversed by the competitive NMDA antagonist AP5, and thus appears to be receptor-mediated. In a separate experiment, lower concentrations of NMDA (20-100 microM) yielded a high correlation (r = 0.96; P < 0.05) of velocity versus concentration. Kainic acid (10 microM) also was found to increase the initial rate of uptake, from 505 +/- 34 to 702 +/- 71 pmol/s per g (P < 0.05). The results of this study indicate that the rate of DA uptake in the striatum can be modulated in vitro by presynaptic ionotropic glutamate receptors.
Welch
S M
SM
Department of Chemistry, Emory University, Atlanta, GA 30322, USA.
Justice
J B
JB
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D018492:Dopamine Antagonists / Q000494:pharmacology; D004594:Electrophysiology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D007608:Kainic Acid / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D016202:N-Methylaspartate / Q000378:metabolism / Q000494:pharmacology; D017072:Neostriatum / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000378:metabolism*; D017661:Receptors, Presynaptic / Q000187:drug effects
D018492:Dopamine Antagonists; D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D017661:Receptors, Presynaptic; D016202:N-Methylaspartate; D015763:2-Amino-5-phosphonovalerate; D007608:Kainic Acid; D004298:Dopamine