Linked Life Data

6150070

Source:http://linkedlifedata.com/resource/pubmed/id/6150070

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1984-12-27
pubmed:abstractText
Dopamine (DA) neurons have been recorded in vivo in four states of activity: hyperpolarized, nonfiring; single spike firing; burst firing; and depolarization inactivation. Nonfiring DA neurons can be made to fire by iontophoretic application of the excitatory substances glutamate and cholecystokinin, or by depolarizing current injection. Spontaneously active DA cells typically fire in a slow (3 to 8 Hz) irregular pattern. In vivo intracellular recordings revealed that this pattern is sustained by the alternation of two currents: a spontaneously occurring slow depolarization (13 +/- 3 mV amplitude, 78 +/- 40 msec duration) which brings the membrane potential of the DA cell to spike threshold (-42 mV), and an afterhyperpolarization mediated by a calcium-activated potassium conductance (IK(Ca)). The slow depolarization is a pacemaker-like conductance, with a rate of rise proportional to the membrane potential. The regular pacemaker pattern of the spontaneously occurring slow depolarization is interrupted by the IK(Ca) which appears to be triggered by calcium entry during the action potential. Thus, intracellular injection of the calcium chelator EGTA will cause DA cells to fire in a regular, pacemaker pattern. The IK(Ca) is observed after single spikes and trains of spikes with the amplitude of the afterhyperpolarization being proportional to the number of spikes in a train. Both the afterhyperpolarization and the firing accommodation observed during depolarizing current injection can be blocked by intracellular injection of the calcium chelator EGTA.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0270-6474
pubmed:author
pubmed:issnType
Print
pubmed:volume
4
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2866-76
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
The control of firing pattern in nigral dopamine neurons: single spike firing.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't