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早在1883年,Ringer氏就已确定了Ca~(++)对心肌收缩的重要性。Ca~(++)与肌肉收缩的关系以及冠脉张力的关系等,均为以后学者证实和重视。本文仅就钙离子拮抗剂的主要临床作用和在心血管疾病的应用作一综述。一、钙离子对心肌的生理作用哺乳动物心肌兴奋性依赖于心肌细胞离子通道的开放。细胞膜内向电流离子通道有三种:运转Na~+为主的快通道,运转Ca~(++)为主的慢通道和Mg~(++)通道。三者均可分别被特殊物质选择性阻滞。快慢电流在动作电位动力学上表现截然不同,因此其病理意义也不相同。病理情况下,随着快反应被抑制,传导速度显著减慢,起搏电流完全以慢反应的慢电流(Isi)为基础,有利于折返
As early as 1883, Ringer had determined the importance of Ca ~ (++) on myocardial contractility. The relationship between Ca ~ (++) and muscle contraction and the relationship between coronary tension and so on are confirmed and emphasized by later scholars. This article reviews only the main clinical role of calcium antagonists and their use in cardiovascular disease. First, the physiological role of calcium ions on the myocardium Mammalian cardiac excitability depends on the opening of myocardial ion channels. There are three types of current channels in the cell membrane: Na ~ + -based fast channels, Ca ~ (++) -based slow channels and Mg ~ (++) channels. Three can be selectively blocked by special substances. Fast current in the action potential dynamics are completely different, so its pathological significance is not the same. Under pathological conditions, as the fast response is suppressed, the conduction velocity is significantly slowed down and the paced current is based solely on the slow-reacting slow current (Isi), favoring reentry