Mukumov M R, Isaeva S A, Belaya M L, Pratusevich V R
Research Institute for Biotechnology, Moscow, Russia.
Gen Physiol Biophys. 1992 Dec;11(6):523-33.
Static and dynamic chrono-inotropic responses were recorded from both normal and hypertrophic rat auricular myocardium. The slope of the static force-frequency relation for hypertrophic hearts was steeper than that for control hearts. Computer experiments were designed to study the cellular mechanisms underlying the changes in the force-frequency response associated with heart hypertrophy, with the aid of a mathematical model for excitation-contraction coupling in rat heart. A set of equations was derived which permitted to study the effects on the chronoinotropic relations of both the geometrical dimensions of cardiomyocytes and the sarcoplasmic reticulum, and of the variation in activity of mechanisms for Ca movements through the sarcolemma and the sarcoreticular membrane. A comparison of data obtained from simulated and real experiments suggested that the features characteristic of force-frequency relations for hypertrophic heart are a result of an enhanced volume of intracellular Ca-stores rather than of the total volume of the cardiomyocyte.
记录了正常和肥大大鼠心房肌的静态和动态变时性肌力反应。肥大心脏的静态力-频率关系斜率比对照心脏的更陡。借助大鼠心脏兴奋-收缩偶联的数学模型，设计了计算机实验来研究与心脏肥大相关的力-频率反应变化的细胞机制。推导了一组方程，用于研究心肌细胞和肌浆网的几何尺寸以及钙通过肌膜和肌浆网的运动机制活性变化对变时性肌力关系的影响。对模拟实验和实际实验获得的数据进行比较表明，肥大心脏力-频率关系的特征是细胞内钙储存量增加而非心肌细胞总体积增加的结果。
