Linked Life Data

11249878

Source:http://linkedlifedata.com/resource/pubmed/id/11249878

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2001-3-16
pubmed:abstractText
Knowledge of the initiation of electrical and contractile activity in the embryonic heart relies to a large extent on data obtained in chicken. In recent years, molecular biological techniques have raised an interest in mouse physiology, including early embryonic development. We studied action potentials and the occurrence of one of the pacemaker currents, I(f), by the whole-cell voltage and current-clamp technique at the earliest stage at which a regular heartbeat is established (9.5 days postcoitum) and at 1 day before birth. We show, first, that at the early stage there is a prominent I(f) in mouse embryonic ventricles, which decreases by 82% before birth in concert with the loss of regular spontaneous activity of ventricular cells. Second, the decrease in I(f) current is associated with a slight change in channel gating kinetics and a decrease in total mRNA expression of the genes encoding for I(f) current. Third, the most prevalent mRNA subtype is switched from HCN4 to HCN2 during the second half of embryonic development. Fourth, the I(f) current may be modulated by the beta-adrenergic cascade, although the coupling to the beta-adrenoceptor in the sarcolemma itself is not yet mature. We conclude that I(f) current of the sinus node type is present in early embryonic mouse ventricular cells. In association with a loss of I(f) current, the ventricle tends to lose pacemaker potency during the second half of embryonic development.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1524-4571
pubmed:author
pubmed:issnType
Electronic
pubmed:day
16
pubmed:volume
88
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
536-42
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
I(f) current and spontaneous activity in mouse embryonic ventricular myocytes.
pubmed:affiliation
Department of Circulation, Division of Regulation of Organ Function, Research Institute of Environmental Medicine, Nagoya University, Japan. kenji@riem.nagoya-u.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't