Document Detail

Inactivation of L-type calcium channels in cardiomyocytes. Experimental and theoretical approaches.
MedLine Citation:
PMID:  15113117     Owner:  NLM     Status:  MEDLINE    
The L-type calcium current (ICa) plays an important role in excitation-contraction coupling of heart cells. It is critical for forming the major trigger for Ca(2+)-induced Ca(2+) release from the sarcoplasmic reticulum and hence its feedback regulation is of fundamental biological significance. The channel inactivation sharpens the kinetics and temporal precision of the Ca(2+) signals so that it prevents longer-term increases in free intracellular Ca(2+) concentration. Cardiac L-type Ca(2+) channels are known to inactivate through voltage- and Ca(2+)-dependent mechanisms. Pure voltage-dependent inactivation has a much slower time course of development than Ca(2+)-dependent inactivation and plays minor role in inhibition of Ca(2+) influx into the cell. The major determinant of the inactivation kinetics of Ca(2+) current during depolarization is Ca(2+)-dependent mechanisms. Furthermore, it is possible to distinguish two phases in Ca(2+)-dependent inactivation of calcium current: a slow phase that depends on Ca(2+) flow through the channels (Ca(2+) current-dependent inactivation) and a fast one that depends on Ca(2+) released from the sarcoplasmic reticulum (Ca(2+) release-dependent inactivation). Although both Ca(2+) released from the SR and Ca(2+) permeating channels play a role, SR-released Ca(2+) is the most effective inactivation mechanism in inhibition of Ca(2+) entry through the channel.
Z Kubalová
Related Documents :
19035847 - Photoproteins: important new tools in drug discovery.
12767887 - Measurement of the dissociation constant of fluo-3 for ca2+ in isolated rabbit cardiomy...
17447907 - Ethylene activates a plasma membrane ca(2+)-permeable channel in tobacco suspension cells.
19679287 - Molecular mri of early thrombus formation using a bimodal alpha2-antiplasmin-based cont...
12871827 - Delphinidin, an active compound of red wine, inhibits endothelial cell apoptosis via ni...
2413917 - Delayed rectification in the calf cardiac purkinje fiber. evidence for multiple state k...
Publication Detail:
Type:  Journal Article; Review    
Journal Detail:
Title:  General physiology and biophysics     Volume:  22     ISSN:  0231-5882     ISO Abbreviation:  Gen. Physiol. Biophys.     Publication Date:  2003 Dec 
Date Detail:
Created Date:  2004-04-28     Completed Date:  2004-08-24     Revised Date:  2005-11-16    
Medline Journal Info:
Nlm Unique ID:  8400604     Medline TA:  Gen Physiol Biophys     Country:  Slovakia    
Other Details:
Languages:  eng     Pagination:  441-54     Citation Subset:  IM    
Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovakia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Calcium / metabolism*
Calcium Channels, L-Type / physiology*
Ion Channel Gating / physiology*
Membrane Potentials / physiology
Models, Cardiovascular*
Myocardial Contraction / physiology*
Myocytes, Cardiac / physiology*
Sarcoplasmic Reticulum / physiology*
Reg. No./Substance:
0/Calcium Channels, L-Type; 7440-70-2/Calcium

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

Previous Document:  Structure and composition of tubular aggregates of skeletal muscle fibres.
Next Document:  Evaluation of human erythrocytes as model cells in photodynamic therapy.