Nanomolar concentrations of kynurenic acid reduce extracellular dopamine levels in the striatum.
Precise regulation of dopaminergic activity is of obvious importance for the physiology and pathology of basal ganglia. We report here that nanomolar concentrations of the astrocyte-derived neuroinhibitory metabolite kynurenic acid (KYNA) potently reduce the extracellular levels of striatal dopamine in unanesthetized rats in vivo. This effect, which is initiated by the KYNA-induced blockade of alpha7 nicotinic acetylcholine receptors, highlights the functional relevance of glia-neuron interactions in the striatum and indicates that even modest increases in the brain levels of endogenous KYNA are capable of interfering with dopaminergic neurotransmission.
Rassoulpour
Arash
A
Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland 21218, USA.
Wu
Hui-Qiu
HQ
Ferre
Sergi
S
Schwarcz
Robert
R
D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D045604:Extracellular Fluid / Q000187:drug effects* / Q000378:metabolism; D007736:Kynurenic Acid / Q000008:administration & dosage*; D008297:Male; D036103:Nanotechnology / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley
D007736:Kynurenic Acid; D004298:Dopamine