Ionic currents activated during hyperpolarization of single right atrial myocytes from cat heart.
Ionic currents activated during hyperpolarization of single right atrial myocytes from cat heart.
复制标题
来自猫心脏的单个右心房肌细胞超极化期间激活的离子电流。
DOI：
10.1161/01.res.68.4.1059
复制
发表时间：
1991
影响因子：
20.1
通讯作者：
Lipsius,SL
中科院分区：
文献类型：
--
作者：
Wu,JY;Vereecke,J;Carmeliet,E;Lipsius,SL
全细胞记录技术应用于单个右心房肌细胞，研究可能导致心房组织不同舒张电压特性的离子电流。离子电流由负至-30 mV的超极化电压脉冲激活。总的来说，四种不同类型的细胞主要是根据超极化过程中产生的离子电流来确定的。第一种细胞类型表现出向内电流，在更负的电压下随时间衰减，在钾平衡电位附近逆转，在更正的电压下向内整流，在细胞外钾升高时增加，并被3mm的钡或10mm的铯阻断。这个电流被确定为钾电流iK1。第二种类型的电池表现出时间依赖的内向电流，在更负的电压下增加，激活范围在-50和-110 mV之间，反转电位为-26 mV，并被3mm铯阻断。这种电流被确定为中频电流。第三种细胞类型表现出一种向内的电流，最初衰减，然后随着时间的推移变得更内向。钡（3mm）消除了初始的向内电流，并显示出一个随时间增加的向内电流，该电流被3mm的铯阻挡。这个电流是由iK1和if电流组成的。第四种类型的电池在响应超极化时仅表现出较小的时间无关泄漏电流。这些结果表明，右心房内的单个细胞在电生理上是不均匀的，就其肌层膜中存在的离子通道类型而言。这种离子电流的专门化部分解释了心房组织不同的舒张电压特征和功能特性。
Whole-cell recording techniques were used on single right atrial myocytes to study the ionic currents that may be responsible for the diverse diastolic voltage characteristics of atrial tissue. Ionic currents were activated by hyperpolarizing voltage pulses negative to -30 mV. In general, four different types of cells were identified based primarily on the ionic currents elicited during hyperpolarization. The first cell type exhibited an inward current that decayed with time at more negative voltages, reversed near the potassium equilibrium potential, inwardly rectified at more positive voltages, increased in elevated extracellular potassium, and was blocked by 3 mM barium or 10 mM cesium. This current was identified as the potassium current iK1. A second cell type exhibited a time-dependent inward current that increased at more negative voltages, had an activation range between -50 and -110 mV, had a reversal potential of -26 mV, and was blocked by 3 mM cesium. This current was identified as an if current. A third cell type exhibited an inward current that initially decayed and then became more inward with time. Barium (3 mM) abolished the initial inward current and revealed a time-dependent increasing inward current that was blocked by 3 mM cesium. This current was composed of both the iK1 and if currents. A fourth cell type exhibited only small time-independent leak currents in response to hyperpolarization. These results indicate that individual cells within the right atrium are electrophysiologically heterogeneous with respect to the types of ionic channels present in their sarcolemmal membranes. This specialization in ionic currents partially explains the diverse diastolic voltage characteristics and functional properties of atrial tissue.
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影响因子：
5.5
作者：
DENYER, JC;BROWN, HF
通讯作者：
BROWN, HF
DOI：
10.1016/s0022-2828(87)80531-x
发表时间：
1987-12-01
影响因子：
5
作者：
HEIDBUCHEL, H;VEREECKE, J;CARMELIET, E
通讯作者：
CARMELIET, E
人心房中三种不同的钾通道。
影响因子：
20.1
作者：
H. Heidbuchel;J. Vereecke;E. Carmeliet
通讯作者：
E. Carmeliet
在单个心脏起搏器细胞中产生自发舒张去极化的离子电流。
DOI：
--
发表时间：
1985
影响因子：
11.1
作者：
E. Shibata;W. Giles
通讯作者：
W. Giles
DOI：
10.2170/jjphysiol.34.245
发表时间：
1984-01-01
期刊：
JAPANESE JOURNAL OF PHYSIOLOGY
影响因子：
--
作者：
NOMA, A;NAKAYAMA, T;IRISAWA, H
通讯作者：
IRISAWA, H