Berdeja García G Y, Pastelín G
Arch Inst Cardiol Mex. 1982 Nov-Dec;52(6):453-60.
In order to relate the cardiac antiarrhytmic properties of magnesium chloride (MgCl2) to its electrophysiological effects, a comparison of its actions on three different models of automaticity of the isolated Purkinje fibers of the dog, has been carried out. The spontaneous activity of the Purkinje fibers perfused with Tyrode's solution containing 2.7 mM KC1 was gradually reduced as MgC12 concentration was increased from 3 to 9 mM/1. The automaticity induced adding barium chloride (BaC12) to the perfusion solution was suppressed increasing the concentration of MgC12 in the Tyrode's solution up to 5 mM/1. Previous increases in the concentration of MgCl2 prevents the electrophysiological effects BaC12. The negative chronotropic effects of MgC12, were less evident on the adrenalin induced automaticity of the Purkinje fibers. Simultaneous addition of adrenalin and MgC12 to the perfusion media increases membrane resting potential action potential amplitude and maximun rate of depolarisation of phase O in Purkinje fibers. It is concluded that MgC12 acts by distinct electrophysiological mechanisms against the different models of cardiac automaticity studied. This findings may provide interesting perspective in respect to the therapeutic properties of magnesium chloride.
为了将氯化镁（MgCl2）的心脏抗心律失常特性与其电生理效应联系起来，对其作用于犬离体浦肯野纤维三种不同自动节律模型的情况进行了比较。当MgC12浓度从3 mM/1增加到9 mM/1时，用含2.7 mM KC1的台氏液灌注的浦肯野纤维的自发活动逐渐降低。向灌注液中添加氯化钡（BaC12）所诱导的自动节律，在台氏液中MgC12浓度增加到5 mM/1时受到抑制。先前MgCl2浓度的增加可防止BaC12的电生理效应。MgC12对肾上腺素诱导的浦肯野纤维自动节律的负性变时作用不太明显。同时向灌注介质中添加肾上腺素和MgC12可增加浦肯野纤维的膜静息电位、动作电位幅度和0期最大去极化速率。得出的结论是，MgC12通过不同的电生理机制作用于所研究的不同心脏自动节律模型。这一发现可能为氯化镁的治疗特性提供有趣的观点。
