Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2000-3-16
pubmed:abstractText
Amperometry with carbon-fiber microelectrodes provides a unique way to measure very small chemical concentration changes at the surface of biological cells. In this work, an investigation of dopamine release from individual neurons isolated from the mouse retina is described. The mice were genetically modified so that, in cells that expressed the protein responsible for catecholamine synthesis, tyrosine hydroxylase, the marker protein, placental alkaline phosphatase, was also expressed. This modification allowed for identification of the dopamine-containing cells among the many present in the freshly dissociated retina. Release of dopamine was evoked by chemical secretagogues delivered from micropipets that were calibrated with respect to response time and concentration delivered. Amperometric measurements were recorded with low-noise patch clamp amplifiers, and the primary noise source was found to be the electrode capacitance. Dopamine release occurred in the form of transient concentration spikes, consistent with release from small intracellular vesicles. With optimized filtering of the data, the quantity secreted during each release event could be determined. The average quantity determined at one cell was 52 zmol. However, the spikes were quite variable in size and the amount released per event ranged from 8 to 170 zmol. These measurements allow an estimation of the concentration of released transmitter in a synapse.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0003-2700
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
72
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
489-96
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Real-time amperometric measurements of zeptomole quantities of dopamine released from neurons.
pubmed:affiliation
Department of Chemistry, University of North Carolina at Chapel Hill 27599-3290, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.