Document Detail


Functional and clinical characterization of KCNJ2 mutations associated with LQT7 (Andersen syndrome).
MedLine Citation:
PMID:  12163457     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Andersen syndrome (AS) is a rare, inherited disorder characterized by periodic paralysis, long QT (LQT) with ventricular arrhythmias, and skeletal developmental abnormalities. We recently established that AS is caused by mutations in KCNJ2, which encodes the inward rectifier K(+) channel Kir2.1. In this report, we characterized the functional consequences of three novel and seven previously described KCNJ2 mutations using a two-microelectrode voltage-clamp technique and correlated the findings with the clinical phenotype. All mutations resulted in loss of function and dominant-negative suppression of Kir2.1 channel function. In mutation carriers, the frequency of periodic paralysis was 64% and dysmorphic features 78%. LQT was the primary cardiac manifestation, present in 71% of KCNJ2 mutation carriers, with ventricular arrhythmias present in 64%. While arrhythmias were common, none of our subjects suffered sudden cardiac death. To gain insight into the mechanism of arrhythmia susceptibility, we simulated the effect of reduced Kir2.1 using a ventricular myocyte model. A reduction in Kir2.1 prolonged the terminal phase of the cardiac action potential, and in the setting of reduced extracellular K(+), induced Na(+)/Ca(2+) exchanger-dependent delayed afterdepolarizations and spontaneous arrhythmias. These findings suggest that the substrate for arrhythmia susceptibility in AS is distinct from the other forms of inherited LQT syndrome.
Authors:
Martin Tristani-Firouzi; Judy L Jensen; Matthew R Donaldson; Valeria Sansone; Giovanni Meola; Angelika Hahn; Said Bendahhou; Hubert Kwiecinski; Anna Fidzianska; Nikki Plaster; Ying-Hui Fu; Louis J Ptacek; Rabi Tawil
Related Documents :
15922277 - The perplexing complexity of cardiac arrhythmias: beyond electrical remodeling.
2580247 - Dialysis-induced cardiac arrhythmias: fact or fiction? importance of preexisting cardia...
7507637 - Continuous electrocardiographic monitoring for more than one hour does not improve the ...
201997 - Arrhythmogenic effects of acute free fatty acid mobilization on ischemic heart.
17998797 - The dependence of successful resuscitation on electrocardiographically documented cardi...
22231937 - Can quantitative regional myocardial dynamics contribute to the differential diagnosis ...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of clinical investigation     Volume:  110     ISSN:  0021-9738     ISO Abbreviation:  J. Clin. Invest.     Publication Date:  2002 Aug 
Date Detail:
Created Date:  2002-08-06     Completed Date:  2002-09-24     Revised Date:  2013-04-18    
Medline Journal Info:
Nlm Unique ID:  7802877     Medline TA:  J Clin Invest     Country:  United States    
Other Details:
Languages:  eng     Pagination:  381-8     Citation Subset:  AIM; IM    
Affiliation:
Division of Pediatric Cardiology, University of Utah, Salt Lake City, Utah 84112, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adolescent
Adult
Animals
Arrhythmias, Cardiac
Child
Electrophysiology
Female
Heart / physiopathology
Heart Defects, Congenital
Humans
Long QT Syndrome / genetics*,  physiopathology
Male
Middle Aged
Mutation*
Paralyses, Familial Periodic / genetics*,  physiopathology
Potassium Channels, Inwardly Rectifying / genetics*,  physiology
Rabbits
Syndrome
Grant Support
ID/Acronym/Agency:
HL-38616/HL/NHLBI NIH HHS; M01-RR-00044/RR/NCRR NIH HHS; RR-00064/RR/NCRR NIH HHS
Chemical
Reg. No./Substance:
0/Potassium Channels, Inwardly Rectifying
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  In vivo bradykinin B2 receptor activation reduces renal fibrosis.
Next Document:  Thrombopoietin expands hematopoietic stem cells after transplantation.