在猫心室肌细胞中,由 flecainide 和 E-4031 阻断延迟整流器电流, IK
1Cardiovascular Pharmacology, Wyeth-Ayerst Research, Princeton, NJ 08543-8000.
Circulation
|July 1, 1990
概括
弗莱卡尼德和E-4031都阻断了延迟的整流器电流 (IK). 这个IK块是E-4031的关键.
科学领域:
- 心血管药理学心血管药理学
- 电子生理学 电子生理学
- 心脏离子通道是什么?
背景情况:
- 延迟的整流电流 (IK) 对于心脏再极化至关重要.
- 抗心律不整的药物可以调节离子通道功能,恢复正常的心律.
研究的目的:
- 为了比较flekainide (IC类) 和E-4031 (III类) 对猫室内肌细胞中的IK的影响.
- 阐明这些药物的抗节律性质背后的机制.
主要方法:
- 使用了孤立的猫室内肌细胞.
- 采用了单吸管子电压技术.
- 评估了Flecainide和E-4031对IK和IK1的影响.
主要成果:
- 弗莱卡尼德 (10微米) 和E-4031 (1微米) 均显著阻断了IK.
- 弗莱卡尼德和E-4031分别显示了93%和96%的IK阻断.
- 两种药物都没有影响背景电流 (IK1).
结论:
- 阻断 IK 是一个共享的机制为 flecainide 和 E-4031.
- 通过E-4031阻断IK可能解释了其强大的III类抗心律失常作用.
- 弗莱卡尼德的IK阻断可以通过Na+通道阻断来抵消,从而保持动作潜力的持续时间.
更多相关视频
07:42Contractions of Human-iPSC-derived Cardiomyocyte Syncytia Measured with a Ca-sensitive Fluorescent Dye in Temperature-controlled 384-well Plates
Published on: October 18, 2018
10:01High-Throughput Optical Controlling and Recording Calcium Signal in iPSC-Derived Cardiomyocytes for Toxicity Testing and Phenotypic Drug Screening
Published on: March 31, 2022
相关概念视频
Depolarizing Blockers: Mechanism of Action
Depolarizing blockers act on skeletal muscle fibers' membranes and induce their depolarization. Most depolarizing blockers have two quaternary N+ atoms that bind the nicotinic acetylcholine receptors and cause neuromuscular blockade within minutes.
Succinylcholine is the most commonly used depolarizing blocker. Chemically, it constitutes two molecules of acetylcholine joined together by an acetate methyl group. They act on the receptors in the same way as acetylcholine. Because succinylcholine...
Succinylcholine is the most commonly used depolarizing blocker. Chemically, it constitutes two molecules of acetylcholine joined together by an acetate methyl group. They act on the receptors in the same way as acetylcholine. Because succinylcholine...
Antiarrhythmic Drugs: Class I Agents as Sodium Channel Blockers
Class I antiarrhythmic drugs are used to treat various types of arrhythmias or irregular heart rhythms. These drugs block the sodium (Na+) channels in the cardiac cells, thereby affecting the movement of electrical impulses across the heart. Class I antiarrhythmic drugs are divided into three subgroups: Class IA, Class IB, and Class IC, each with distinct mechanisms of action and effects on the heart.
Class 1A Antiarrhythmic Drugs: These drugs work by moderately blocking sodium channels,...
Class 1A Antiarrhythmic Drugs: These drugs work by moderately blocking sodium channels,...
Heart Failure Drugs: Inotropic Agents
Positive inotropic agents are commonly used as the first line of treatment for heart failure. One such agent is digoxin, derived from the genus Digitalis, which has been known for centuries but effectively utilized since 1785. However, these cardiac glycosides can have potentially toxic effects due to their mechanism of action, which involves inhibiting Na+/K+-ATPase and increasing contractility. Digoxin is absorbed orally and distributed in various tissues, including the CNS. It has a long...
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
Arrhythmia is a condition characterized by an irregular heart rhythm, with ECG changes that differ based on its origin and nature. The types of arrhythmias discussed below include atrial, junctional, and ventricular arrhythmias.Atrial ArrhythmiasPremature Atrial Complexes (PACs): PACs are early atrial beats caused by stress, caffeine, alcohol, electrolyte imbalances, hypoxia, hyperthyroidism, or certain medications (e.g., bronchodilators and decongestants). The ECG shows early P waves with an...
