Reserch Of The Effects Of Intermedin On Ventricular Arrhythmia In Rat Heart During Ischemia And Reperfusion

Objective:To observe the effect of intermedin(IMD)on ventricular arrhythmia and try to investigate the underlying mechanisms.Metholds: 1.The role of IMD in ventricular arrhythmias during myocardial ischemia and reperfusionThirty Sprague-Dawley(SD)rats were randomly divided into 3 groups:(1)sham operation group,(2)ischemia and reperfusion group,(3)IMD group.We monitored the electrocardiogram to record the occurrence and severity of ventricular arrhythmias during ischemia and reperfusion.HE staining was used to observe the myocardial path-histology injury under the light microscope.2.Detecting the effect of IMD in the phosphorylation status and distribution of Cx43 during myocardial ischemia and reperfusionWestern blot was used to detect the change of phosphorylation status of Cx43.Immunofluorescence was used to detect the change of diatribution of Cx43.3.Investigate the relationship between the PKC and PKA pathway and the effect of IMD on Cx43The rats were treatment with the PKC inhibitor CHE or the PKA inhibitor H89 with the IMD prior to the myocardial ischemia and reperfusion.Monitoring the electrocardiogram to record the occurrence and severity of ventricular arrhythmias during ischemia and reperfusion.Using the HE staining to observe the myocardial path-histology injury under the light microscope.Using the Western blot to detect the change of phosphorylation status of Cx43.Immunofluorescence was used to detect the change of diatribution of Cx43.Results: 1.IMD decreased the occurrence and severity of ventricular arrhythmias during ischemia and reperfusion and reduced the myocardial path-histology injury during ischemia and reperfusion.2.IMD inhibited the change of phosphorylation status and distribution of Cx43 during myocardial ischemia and reperfusion.3.The PKC inhibitor and PKA inhibitor abolished the effect of IMD on the ventricular arrhythmias during ischemia and reperfusion and the effect on the change of phosphorylation status and the redistribution of Cx43.Conclusion: Intermedin antagonizes ventricular arrhythmias during myocardial ischemia and reperfusion via regulating the phosphorylation and distribution of Cx43 induced by activating PKC and PKA pathway.