Changes in cell-to-cell electrical coupling associated with left ventricular hypertrophy.
Changes in cell-to-cell electrical coupling associated with left ventricular hypertrophy.
复制标题
与左心室肥厚相关的细胞间电耦合的变化。
作者：
M. Cooklin;W. Wallis;DJ Sheridan;C. Fry
在20℃和37℃条件下，利用主动脉收缩肥厚心脏组织测量豚鼠左室心肌细胞间室电流阻抗。不同频率的交流电沿心肌制剂纵向传递，揭示了两个时间常数：一个归因于制剂末端的表面膜，另一个位于细胞内通路。根据平行的细胞内和细胞外通路定量分析纵向阻抗；前者有两个系列成分，一个归因于细胞质，另一个归因于相邻细胞之间的低电阻连接。这一解释与(1)使用正庚醇的对照实验是一致的，正庚醇增加了归因于细胞间连接的成分，而不是肌浆电阻率，(2)与分离的肌细胞悬浮液是一致的，这产生了类似的肌浆电阻率值。主动脉收缩使实验动物的心脏重量/体重比从收缩50天后的平均值3.10 +/- 0.28增加到5.05 +/- 0.83 g/kg，收缩150天后的5.60 +/- 0.95 g/kg。收缩150天心脏重量与体重比的增加与细胞内电阻率的增加有关，这可以仅仅归因于相邻细胞之间的连接电阻在20℃时增加了约44%，在37℃时增加了140%；肌浆电阻率不变。结果讨论了在肥厚的心肌传导改变作为一个可能的基础心律失常在该组织。
The impedance to current flow in the intracellular compartment of guinea pig left ventricular myocardium was measured at 20 degrees C and 37 degrees C using tissue from hypertrophied hearts subjected to aortic constriction. Alternating current of varying frequency was passed longitudinally along myocardial preparations, which revealed two time constants: one attributed to the surface membrane at the ends of the preparation and a second lying in the intracellular pathway. The longitudinal impedance was quantitatively analyzed in terms of a parallel intracellular and extracellular pathway; the former had two series components, one attributable to the sarcoplasm and the other to the low-resistance junctions between adjacent cells. This interpretation was consistent (1) with control experiments using n-heptanol, which increased the component attributed to intercellular junctions but not sarcoplasmic resistivity, and (2) with suspensions of isolated myocytes, which yielded a similar value for the sarcoplasmic resistivity. Aortic constriction increased the heart weight-to-body weight ratio of experimental animals from a mean value of 3.10 +/- 0.28 to 5.05 +/- 0.83 g/kg after 50 days of constriction and 5.60 +/- 0.95 g/kg after 150 days of constriction. An increase of heart weight-to-body weight ratio at 150 days of constriction was associated with an increased intracellular resistivity, which could be attributed solely to an increase of the junctional resistance between adjacent cells by approximately 44% at 20 degrees C and 140% at 37 degrees C; the sarcoplasmic resistivity was unchanged. The results are discussed in terms of altered conduction in hypertrophied myocardium as a possible basis for arrhythmias in this tissue.
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影响因子：
20.1
作者：
DARROW, BJ;LAING, JG;BEYER, EC
通讯作者：
BEYER, EC
影响因子：
20.1
作者：
BRILLA, CG;PICK, R;WEBER, KT
通讯作者：
WEBER, KT
平滑肌细胞间电耦合的变化伴随着萎缩和肥大。
DOI：
10.1152/ajpcell.1986.250.2.c292
发表时间：
1986
期刊：
The American journal of physiology
影响因子：
--
作者：
Bortoff,A;Sillin,LF
通讯作者：
Sillin,LF
肢端肥大症大鼠心室肌细胞中瞬时外向 K 电流减少。
DOI：
10.1152/ajpheart.1991.260.3.h935
发表时间：
1991
期刊：
The American journal of physiology
影响因子：
--
作者：
Xu,XP;Best,PM
通讯作者：
Best,PM