Action potential propagation in inhomogeneous cardiac tissue: safety factor considerations and ionic mechanism.
Action potential propagation in inhomogeneous cardiac tissue: safety factor considerations and ionic mechanism.
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不均匀心脏组织中的动作电位传播：安全因素考虑和离子机制。
DOI：
10.1152/ajpheart.2000.278.4.h1019
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Rudy,Y
中科院分区：
文献类型：
--
作者：
Wang,Y;Rudy,Y
Heterogeneity of myocardial structure and membrane excitability is accentuated by pathology and remodeling. In this study, a detailed model of the ventricular myocyte in a multicellular fiber was used to compute a location-dependent quantitative measure of conduction (safety factor, SF) and to determine the kinetics and contribution of sodium current (INa) and L-type calcium current [ICa(L)] during conduction. We obtained the following results.1) SF decreases sharply for propagation into regions of increased electrical load (tissue expansion, increased gap junction coupling, reduced excitability, hyperkalemia); it can be <1 locally (a value indicating conduction failure) and can recover beyond the transition region to resume propagation.2) SF and propagation across inhomogeneities involve major contribution fromICa(L).3) ModulatingINaorICa(L)(by blocking agents or calcium overload) can cause unidirectional block in the inhomogeneous region.4) Structural inhomogeneity causes local augmentation ofICa(L)and suppression ofINain a feedback fashion.5) Propagation across regions of suppressedINais achieved via aICa(L)-dependent mechanism.6) Reduced intercellular coupling can effectively compensate for reduced SF caused by tissue expansion but not by reduced membrane excitability.
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影响因子：
20.1
作者：
LUO, CH;RUDY, Y
通讯作者：
RUDY, Y
DOI：
10.1111/j.1540-8167.1999.tb00645.x
发表时间：
1999-01-01
影响因子：
2.7
作者：
Huang, XD;Sandusky, GE;Zipes, DP
通讯作者：
Zipes, DP
影响因子：
20.1
作者：
Spach,MS;Heidlage,JF
通讯作者：
Heidlage,JF
影响因子：
37.8
作者：
N. Peters;J. Coromilas;N. Severs;A. L. Wit
通讯作者：
N. Peters;J. Coromilas;N. Severs;A. L. Wit
影响因子：
20.1
作者：
Pu, JL;Boyden, PA
通讯作者：
Boyden, PA