Linked Life Data

16219869

Source:http://linkedlifedata.com/resource/pubmed/id/16219869

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-12-15
pubmed:abstractText
We investigated the effects of chronic and moderate heart rate (HR) reduction on ion channel expression in the mouse sinoatrial node (SAN) and ventricle. Ten-week-old male C57BL/6 mice were treated twice daily with either vehicle or ivabradine at 5 mg/kg given orally during 3 wk. The effects of HR reduction on cardiac electrical activity were investigated in anesthetized mice with serial ECGs and in freely moving mice with telemetric recordings. With the use of high-throughput real-time RT-PCR, the expression of 68 ion channel subunits was evaluated in the SAN and ventricle at the end of the treatment period. In conscious mice, ivabradine induced a mean 16% HR reduction over a 24-h period that was sustained over the 3-wk administration. Other ECG parameters were not modified. Two-way hierarchical clustering analysis of gene expression revealed a separation of ventricles from SANs but no discrimination between treated and untreated ventricles, indicating that HR reduction per se induced limited remodeling in this tissue. In contrast, SAN samples clustered in two groups depending on the treatment. In the SAN from ivabradine-treated mice, the expression of nine ion channel subunits, including Navbeta1 (-25%), Cav3.1 (-29%), Kir6.1 (-28%), Kvbeta2 (-41%), and Kvbeta3 (-30%), was significantly decreased. Eight genes were significantly upregulated, including K+ channel alpha-subunits (Kv1.1, +30%; Kir2.1, +29%; Kir3.1, +41%), hyperpolarization-activated cation channels (HCN2, +24%; HCN4, +52%), and connexin 43 (+26%). We conclude that reducing HR induces a complex remodeling of ion channel expression in the SAN but has little impact on ion channel transcripts in the ventricle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1531-2267
pubmed:author
pubmed:issnType
Electronic
pubmed:day
14
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4-12
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Chronic heart rate reduction remodels ion channel transcripts in the mouse sinoatrial node but not in the ventricle.
pubmed:affiliation
Institut National de la Santé et de la Recherche Médicale (INSERM), U533, l'Institut du Thorax, Nantes, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't