title: Impulse-dependent extracellular resting dopamine concentration in rat striatum in vivo.
abstract: The ambient resting dopamine (DA) concentration in brain regulates cognition and motivation. Despite its importance, resting DA level in vivo remains elusive. Here, by high-frequency stimulation of the medial forebrain bundle and immediately following the stimulus-induced DA overflow, we recorded a DA "undershoot" which is a temporal reduction of DA concentration to a level below the baseline. Based on the DA undershoot, we predicted a resting DA concentration of ∼73nM in rat striatum in vivo. Simulation studies suggested that removing basal DA by DAT during the post-stimulation inhibition of tonic DA release caused the DA undershoot, and the resting concentration of DA modulated the kinetics of the evoked DA transient. The DA undershoot was eliminated by either blocking D2 receptors with haloperidol or blocking the DA transporter (DAT) with cocaine. Therefore, the impulse-dependent resting DA concentration is in the tens of nanomolar range and is modulated by the presynaptic D2 receptors and the DAT in vivo.
authors.affiliation: State Key Laboratory of Biomembrane and Membrane Biotechnology and the Center for Life Sciences, Institute of Molecular Medicine, Peking University, Beijing 100871, China.
authors.forename: Pan-Li
authors.initials: PL
authors.lastname: Zuo
authors.forename: Wei
authors.initials: W
authors.lastname: Yao
authors.forename: Liang
authors.initials: L
authors.lastname: Sun
authors.forename: Shu-Ting
authors.initials: ST
authors.lastname: Kuo
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
authors.forename: Shi-Rong
authors.initials: SR
authors.lastname: Wang
authors.forename: Hai-Qiang
authors.initials: HQ
authors.lastname: Dou
authors.forename: Hua-Dong
authors.initials: HD
authors.lastname: Xu
authors.forename: Claire Xi
authors.initials: CX
authors.lastname: Zhang
authors.forename: Xin-Jiang
authors.initials: XJ
authors.lastname: Kang
authors.forename: Zhuan
authors.initials: Z
authors.lastname: Zhou
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
mesh_terms: D000465:Algorithms; D000818:Animals; D003042:Cocaine / Q000494:pharmacology; D003198:Computer Simulation; D004298:Dopamine / Q000378:metabolism*; D018492:Dopamine Antagonists / Q000494:pharmacology; D050483:Dopamine Plasma Membrane Transport Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D004558:Electric Stimulation; D004563:Electrochemistry; D005110:Extracellular Space / Q000378:metabolism*; D006220:Haloperidol / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D008474:Medial Forebrain Bundle / Q000502:physiology; D017072:Neostriatum / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017448:Receptors, Dopamine D2 / Q000187:drug effects / Q000378:metabolism
chemical_list: D018492:Dopamine Antagonists; D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors; D017448:Receptors, Dopamine D2; D003042:Cocaine; D006220:Haloperidol; D004298:Dopamine