氯化汞对离体豚鼠心肌的作用

Effects of mercuric chloride on isolated guinea pig myocardium

为研究汞对心脏毒性的机制，采用细胞内固定微电极技术，观察了氯化汞（ＨｇＣｌ２）对离体豚鼠心肌的影响。结果表明：１０μｍｏｌ／Ｌ的ＨｇＣｌ２增加乳头状肌收缩幅度、增强豚鼠乳头状肌自律性、缩短功能不应期（ＦＲＰ）至（１５２±２４）ｍｓ，与对照组比较，差异有显著性（Ｐ＜０．０５）。ＨｇＣｌ２抑制心肌兴奋性。提示：ＨｇＣｌ２阻碍心肌细胞膜离子正常流动，可能是其致心律失常的心脏毒性的重要机制之一。

The effects of mercuric chloride(HgCl 2) on isolated guinea pig myocardium were studied by using conventional intracellular microelectrode method.The results showed that HgCl 2(10 μmol/L) increased the amplitude of contraction and automaticity of papillary muscle in guinea pigs.HgCl 2 also markedly shortened the functional refractory period of papillary muscles to (152±24)ms and decreased the excitability of the myocardium.It is suggested that inhibition of HgCl 2 on normal ion current in cellular membrane of myocardium may be one of the important mechanism of HgCl 2 induced arrhythmic cardiotoxicity.