Simultaneous recording of His bundle electrogram, electrocardiogram, and systolic tension from intact modified Langendorff rat heart preparations. I: effects of perfusion time, cadmium, and lead.
Simultaneous recording of His bundle electrogram, electrocardiogram, and systolic tension from intact modified Langendorff rat heart preparations. I: effects of perfusion time, cadmium, and lead.
复制标题
同时记录完整改良 Langendorff 大鼠心脏制剂的希氏束电图、心电图和收缩压。
DOI：
10.1016/0041-008x(78)90093-5
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发表时间：
1978
影响因子：
3.8
通讯作者：
P. Hawley
中科院分区：
文献类型：
--
作者：
S. J. Kopp;J. Baker;L. S. D'Agrosa;P. Hawley
描述了一种同时记录完整灌流大鼠心脏制剂的希氏束电(HBE)、心电(ECG)和收缩压的方法。这项技术被开发用于离子、药理学和毒理学研究，以确定受控条件下化学试剂对心肌兴奋性和收缩能力的影响。利用完整的离体灌流大鼠心脏的HBE记录技术代表了一种新的方法，可用于研究心脏传导障碍并将其定位于心脏传导系统中的离散位置。心肌收缩能力的相应变化也可以确定，并与观察到的电生理变化相关联。对这些心脏的电和机械事件的时间对照研究表明，在平衡后3小时内，用这种方法灌流的心脏是稳定的。比较镉(3×10−2 mM)和铅(3×10−2 mM Pb2+)对心肌收缩张力和兴奋性的影响。两种离子均能显著降低收缩压，延长心电PR间期。同样，Cd~(2+)和Pb~(2+)显著增加HBE的A-H和H-V传导时间；然而，Cd~(2+)治疗的心脏在A-H间期(房室结抑制)和暴露于Pb2+的心脏的H-V间期(His-Purkinje细胞抑制)内发生传导阻滞。通过结合心电图学、希氏束电图学和峰值收缩能力分析，该技术提供了必要的信息，用于评估镉和铅等毒物和药物的心脏抑制效应，同时将它们的作用部位定位到心脏传导系统中的特定区域。
A method for simultaneously recording His bundle electrograms (HBE), electrocardiograms (ECG), and systolic tensions from intact perfused rat heart preparations is described. This technique was developed for use in ionic, pharmacological, and toxicological studies to determine the effects of chemical agents on myocardial excitability and contractility under controlled conditions. The HBE recording technique using intact isolated perfused rat hearts represents a new method which may be used to study cardiac conduction disturbances and localize them to discrete sites within the cardiac conduction system. Corresponding changes in myocardial contractility also can be determined and correlated with observed electrophysiological alterations. A temporal control study of electrical and mechanical events of these hearts demonstrated the stability of hearts perfused with this method during a 3-hr postequilibrium period. The effects of cadmium (3 × 10−2mm Cd2+) and lead (3 × 10−2mm Pb2+) on myocardial systolic tension and excitability were compared. Both ions significantly depressed systolic tension and prolonged the PR interval of the ECG. Similarly, Cd2+and Pb2+significantly increased A-H and H-V conduction times of the HBE; however, conduction blocks occurred within the A-H interval (atrioventricular nodal depression) in Cd2+-treated hearts and within the H-V interval (His-Purkinje cell depression) of Pb2+-exposed hearts. By combining electrocardiographic, His bundle electrographic and peak systolic contractility analyses, this technique provides the necessary information for evaluating the cardiodepressive effects of toxicological and pharmacological agents, such as cadmium and lead, while localizing their sites of action to specific areas within the cardiac conduction system.