Linked Life Data

11165800

Source:http://linkedlifedata.com/resource/pubmed/id/11165800

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2001-2-22
pubmed:abstractText
Motor neurons are endowed with intrinsic and conditional membrane properties that may shape the final motor output. In the first half of this paper we present data on the contribution of I(h), a hyperpolarization-activated inward cation current, to phase-transition in motor neurons during rhythmic firing. Motor neurons were recorded intracellularly during locomotion induced with a mixture of N-methyl-D-aspartate (NMDA) and serotonin, after pharmacological blockade of I(h). I(h) was then replaced by using dynamic clamp, a computer program that allows artificial conductances to be inserted into real neurons. I(h) was simulated with biophysical parameters determined in voltage clamp experiments. The data showed that electronic replacement of the native I(h) caused a depolarization of the average membrane potential, a phase-advance of the locomotor drive potential, and increased motor neuron spiking. Introducing an artificial leak conductance could mimic all of these effects. The observed effects on phase-advance and firing, therefore, seem to be secondary to the tonic depolarization; i.e., I(h) acts as a tonic leak conductance during locomotion. In the second half of this paper we discuss recent data showing that the neonatal rat spinal cord can produce a stable motor rhythm in the absence of spike activity in premotor interneuronal networks. These coordinated motor neuron oscillations are dependent on NMDA-evoked pacemaker properties, which are synchronized across gap junctions. We discuss the functional relevance for such coordinated oscillations in immature and mature spinal motor systems.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0361-9230
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
53
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
649-59
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Contributions of intrinsic motor neuron properties to the production of rhythmic motor output in the mammalian spinal cord.
pubmed:affiliation
Section of Neurophysiology, Department of Medical Physiology, University of Copenhagen, Copenhagen, Denmark. O.Kiehn@mfi.ku.dk
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't