The Effects Of Lidocaine And Propafenone On Isolated Rat's Cardiac Function

Objective: To study the effects and the mechanism of lidocaine and propafenone on isolated rat's cardiac function.Methods: Using the langendorff technique to investigate the effects of lidocaine and propafenone on left ventricular function in non-ischemia and ischemia group.Results:⑴Lidocaine group: lidocaine was infused at concentrations of 0(control),2.5,5,10 or 20μg/ml for 5 min in perfusion period.①Non-ischemia group : at concentration of 0,2.5,5,10,20μg/ml,lidocaine decreased left ventricular function (0.5±0.1)%,(34.1±5.7)%,(38.0±7.4)%,(44.2±5.1)%,(64.7±6.0)%,respectively;adding 2.5,5,10 or 20μg/ml lidocaine significantly inhibited left ventricular function compared with control (P≤0.001).②Ischemia group: at concentration of 0,2.5,5,10,20μg/ml,lidocaine decreased left ventricular function (86.3±4.4)%,(76.6±6.7)%,(85.6±4.4)%,(92.1±1.8)%,(94.2±3.0)%,respectively;compared with control,adding 2.5μg/ml lidocaine significantly improved left ventricular function(P≤0.01),adding 5 or 10μg/ml lidocaine had no effect on left ventricular function,adding 20μg/ml lidocaine significantly inhibited left ventricular function(P<0.05).⑵Propafenone group: propafenone was infused at concentrations of 0(control),10^-3,10^-2,10^-1 or 1μmol/L for 5 min in perfusion period.①Non-ischemia group : at concentration of 0,10^-3,10^-2,10^-1,1μmol/L,propafenone decreased the cardiac function (0.5±0.1)% , (13.1±2.1)% , (23.1±2.6)% ,(36.3±5.5)%,(46.4±2.5)%,respectively;adding 10^-3,10^-2,10^-1 or 1μmol/L propafenone significantly inhibited left ventricular function compared with control (P≤0.001).②Ischemia group: at concentration of 0,10^-3,10^-2,10^-1,1μmol/L,propafenone decreased the cardiac function (86.3±4.4)%,(73.2±2.4)%,(84.0±3.1)%,(88.4±4.8)%,(90.3±0.3)%,respectively;compared with control,adding 10-3μmol/L propafenone significantly improved left ventricular function(P≤0.001),adding 10^-2,10^-1 or 1μmol/L propafenone had no effect on left ventricular function.Conclusion: Lidocaine and propafenone can inhibit non-ischemic rat's cardiac function concentration -dependently;lidocaine and propafenone can protect ischemic rat's cardiac function at low concentration.