Linked Life Data

9714426

Source:http://linkedlifedata.com/resource/pubmed/id/9714426

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1998-9-3
pubmed:abstractText
The objective of the present work is to study the ionic mechanisms for the regional differences in action potential duration in rat ventricle. This regional diversity has been related to differences in the regional distribution of some potassium currents in several species. Single cells were obtained by enzymatic dispersion of tissue segments from rat ventricular muscle. Whole cell voltage-clamp methods were used to identify the K+ currents involved in action potential repolarisation in the different regions. 4-Aminopiridine, TEA and voltage protocols were used to isolate the following potassium currents: transient outward, Ito, delayed rectifier, Ik, and sustained current, Iss. In the present work, we have studied the distribution of these three repolarising currents, and that of the inward rectifier, Ikl, in the free wall of the right ventricle, the subepicardium of the apex of the left ventricle and in the subendocardium of the base of the left ventricle. Action potential duration was longer in the left than in the right ventricle, and in the former it was longer in the subendocardium of the base than in the subepicardium of the apex. The main difference was in the phase 1, suggesting the implication of Ito. This was confirmed with voltage-clamp experiments. In conclusion, this work shows that Ito current density is higher in the regions with the shorter action potential, whereas there are no differences in the regional distribution of Ik, Iss or Ikl.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0024-3205
pubmed:author
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
391-400
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Differences in regional distribution of K+ current densities in rat ventricle.
pubmed:affiliation
University of the Basque Country, School of Pharmacy, Department of Physiology, Bilbao, Spain. ofpcasao@lg.ehu.es
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't