Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-6-25
pubmed:abstractText
Fast-scan cyclic voltammetry in conjunction with carbon fiber microelectrode has been used to study dopamine (DA) release and uptake mechanisms in rat brains because of the smaller size of the electrode and the subsecond resolution. Current voltammetry data were analyzed by a DA kinetic model assuming a zero baseline, which is in conflict with existing microdialysis findings and a recent claim of the striatal extracellular DA concentration at micromolar levels. This work applied a new analysis approach based on a modified DA kinetic model to analyze the kinetics of electrically evoked DA overflow in the caudate-putamen of anesthetized rats. The DA uptake parameters were fitted from the electrical stimulation phase, and subsequently used to calculate theoretical DA uptake rates. Comparison of the theoretical uptake rates with experimental clearance rates allows for the study of the tonic DA release process following electrical stimulations. Analyses of DA voltammetry data suggest that the locally averaged basal level of extracellular DA in the rat striatum might be confined between 95 and 220 nM. The disparate time scales in the clearance kinetics of endogenous and exogenous DA were investigated. Long-distance diffusion could only partially explain the slow clearance time course of exogenous DA. Model simulations and parameter analyses on evoked DA responses indicate that suppression of the nonevoked DA release process immediately following electrical stimulation cannot completely account for the rapid clearance of the electrically evoked DA. Inconsistency in the measured uptake strengths in the literature studying endogenous and exogenous DA remains to be investigated in the future.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0165-0270
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
164
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27-42
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Extracting the basal extracellular dopamine concentrations from the evoked responses: re-analysis of the dopamine kinetics.
pubmed:affiliation
Department of Chemical & Biomedical Engineering, Florida A&M University-Florida State University College of Engineering, Tallahassee, FL 32310-6046, USA. kevinchen@eng.fsu.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural