[Electrophysiologic effect of magnesium sulphate on arrhythmias].
The effects of MgSO4 on arrhythmia induced by ouabain and on action potentials (AP) and contractile force (Fc) of guinea pig papillary muscles were studied using a glass microelectrode technique. The results showed: 1) MgSO4 4 mmol/L inhibited guinea pig papillary muscle oscillatory after-potential induced by ouabain 0.4 ymol/L; 2) MgSO4 4 mmol/L caused a decrease in spontaneous electric activity in ventricular muscles induced by ouabain 0.8 vmol/L; 3) MgSO4 4 mmol/L had no effect on AP. but decreased the Fe of papillary muscles.