Chronic Partial Occlusion of the Pulmonary Artery in Cats: Change In Ventricular Action Potential Configuration During Early Hypertrophy
Chronic Partial Occlusion of the Pulmonary Artery in Cats: Change In Ventricular Action Potential Configuration During Early Hypertrophy
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猫肺动脉慢性部分闭塞：早期肥大期间心室动作电位配置的变化
DOI：
10.1161/01.res.32.1.15
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发表时间：
1973
影响因子：
20.1
通讯作者：
H. Gelband
中科院分区：
文献类型：
--
作者：
A. Bassett;H. Gelband
本实验测定了压力负荷引起心肌肥厚过程中心肌细胞电活动与力产生的关系。在诱导慢性右室流出道梗阻后，在离体右室乳头肌和肉小梁上监测跨膜电位和最佳长度的等长主动力（Po）。在手术后1、3、7、10、21和> 90天研究了部分肺动脉闭塞或假手术的猫。在Tyrode溶液（36°C）中以30/min以最佳长度刺激右心室肌肉。来自假手术和1天压力负荷心脏的肌肉具有与正常肌肉相似的电和机械特性。1天和3天压力负荷心脏的右心室收缩期峰值和舒张末期压增加; 3、7和10天压力负荷心脏的右心室水百分比增加。与正常肌肉相比，3天压力负荷心室的肌肉有显着降低Po，最大力发展速率，达到峰值力的时间和收缩持续时间，其动作电位平台起源于更多的负电位（平均24.7 mV的11块肌肉）。部分肺动脉阻断后7和10天，肌肉动作电位形态改变不明显，压力负荷后21和> 90天，肌肉动作电位形态改变不明显;然而，Po和最大力量发展率仍然下降，尽管从7、10、21和> 90天的压力负荷心室。
The relation of single cell electrical activity to generation of force was determined for myocardium during the development of hypertrophy induced by pressure loading. Transmembrane potentials and isometric active force at optimal length (Po) were monitored in isolated right ventricular papillary muscles and trabeculae carneae after inducing chronic right ventricular outflow tract obstruction. Cats subjected to partial pulmonary artery occlusion or to sham operation were studied 1, 3, 7, 10, 21, and > 90 days after surgery. Right ventricular muscles were stimulated at 30/min at optimal length in Tyrode's solution (36°C). Muscles from sham-operated and 1 day pressure-loaded hearts had electrical and mechanical properties similar to normal muscles. Right ventricular peak systolic and end-diastolic pressures were increased for 1 and 3 day pressure-loaded hearts; the percent of right ventricular water was increased for 3, 7, and 10 day pressure-loaded hearts. Muscles from 3 day pressure-loaded ventricles had significantly decreased Po, maximum rate of force development, time to peak force, and duration of contraction compared with normal muscles, and their action potential plateaus originated at more negative potentials (mean 24.7 mv for 11 muscles). The alteration in action potential configuration was less obvious in muscles studied 7 and 10 days after partial pulmonary artery occlusion and did not occur 21 and > 90 days after pressure loading; however, Po and maximum rate of force development remained decreased, although time to peak force and duration of contraction returned to normal for preparations from 7, 10, 21, and > 90 day pressure-loaded ventricles.