| Objective:To observe the effects of Mongolian medicine Zandan-3 decoction on heart conduction time,conduction velocity and conduction dispersion in rats,and to analyze the electrocardiogram of rats to explore the effects of Zandan-3 decoction on heart rate,QRS complex,ERP and atrioventricular delay time.To establish a rat model of myocardial ischemia-reperfusion and observe whether the intervention of Zandan-3 decoction has an effect on the probability of ventricular arrhythmia caused by myocardial ischemia-reperfusion,so as to confirm the intervention effect of Zandan-3 decoction on arrhythmia caused by myocardial ischemia-reperfusion and its possible mechanism.Method:(1)Eighteen adult male SD rats were divided into normal group(control,1.25mg/ml,6.25mg/ml,12.5mg/ml Zandan-3 decoction),ischemia-reperfusion model group,and 6.25mg/ml Zandan-3 decoction + ischemia-reperfusion model group.Six rats were randomly assigned to each group.(2)After the extraction of Zandan-3 decoction,1.25mg/ml,6.25mg/ml,12.5mg/ml working solution were prepared and dissolved in KH solution,then the working solution was put into the heart for Langendorff perfusion.The left atrium and left ventricle were recorded by a128-channel matrix electrical mapping system.(3)In the normal group,the conduction time,conduction velocity,conduction dispersion and electrocardiogram of left atrium and left ventricle of isolated rat hearts were observed under the stimulation of S1S2 and 6Hz with Zandan-3 decoction.In the ischemia-reperfusion model group,the occurrence of early after depolarisation and late after depolarisation under 6Hz stimulation and the probability of ventricular arrhythmia induced by 50 Hz stimulation were observed.In the Zandan-3 6.25mg/ml+ ischemia-reperfusion model group,the effect of Zandan-3 decoction on early and late depolarizations after myocardial ischemia-reperfusion and the probability of ventricular arrhythmia was observed.Results:(1)Effect of Zandan-3 decoction on cardiac conduction:(1)At 6Hz stimulation frequency,the left ventricular conduction velocity decreased from 0.87±0.11mm/ms to 0.44±0.06 mm/ms and 0.54±0.05mm/ms at 6.25 and 12.5 mg/ml,respectively,with a significant difference(p <0.05).The conduction time increased from 3.06±0.23 ms to 3.90±0.26 ms and 4.80±0.28 ms,respectively(p < 0.05).(2)In sinus condition,after 12.5 mg/ml Zandan-3 decoction intervention,the left ventricular conduction time was prolonged from 1.14±0.10 to 1.44±0.02 ms,and the conduction velocity was decreased from 2.65±0.23 to 2.05±0.12mm/ms,and the differences were statistically significant(p < 0.05).(3)The analysis of the effect of Zandan-3 decoction on left atrial conduction time showed that the conduction time tended to be prolonged after drug intervention,but there was no significant difference compared with the control group(P > 0.05),and the conduction velocity did not change significantly.All the above drug effects could be recovered by elution.(2)The effect of Zandan-3 decoction on the dispersion of cardiac conduction:(1)Under 6Hz stimulation,the dispersion of 12.5mg/ml Zandan-3 decoction was prolonged from1.02±0.18mm/ms to 1.82±0.12mm/ms,and the difference was significant(p < 0.05).(2)Under sinus condition,all concentrations of Zandan-3 decoction had a tendency to prolong the left atrial conduction dispersion,and 1.25mg/ml Zandan-3 decoction had a tendency to decrease the left ventricular conduction dispersion,but there was no significant difference compared with the control group(P > 0.05).All the above drug effects could be recovered by elution.(3)Effects of Zandan-3 decoction on ECG and ERP in rat heart:(1)The heart rate decreased from 259.80±5.61 BPM to 240.80±3.27 BPM,223.20±5.64 BPM and 188.50±4.93 BPM after1.25,6.25 and 12.5mg/ml Zantan-3 decoction intervention,respectively,and the differences were statistically significant(p < 0.05).(2)Statistical analysis of QRS complex showed that when 6.25mg/ml and 12.5mg/ml Zandan-3 decoction were given,the QRS interval was prolonged from13.33±0.92 ms to 16.00±0.73 ms and 18.00±1.13 ms,respectively,which was significantly different from that of the control group(p < 0.05).It is predicted that Zandan-3 soup may have an effect on Nav1.5 channels.(3)Zandan-3 decoction affected the prolongation of ERP during ventricular repolarization,which was significantly prolonged from 52.00±7.90 to 105.2±6.75 ms after 12.5mg/ml Zandan-3 decoction administration under SIS2 stimulation(p < 0.01).(4)When Zandan-3 decoction 12.5mg/ml was given by perfusion,the atrioventricular delay time was prolonged from 43.67±2.38 to 50.50±1.84 ms,with a significant difference(p < 0.05).All the above drug effects could be recovered by elution.(4)The effect of Zandan-3 decoction on ischemia-reperfusion injury heart:(1)The incidence of ventricular fibrillation in ischemia-reperfusion group was 83.33% when the heart was stimulated with 50 Hz,and the early and late depolarizations occurred under 6Hz stimulation.(2)In the 6.25mg/ml Zantan-3 decoction + ischemia-reperfusion model group,the probability of ventricular fibrillation decreased to 16.67% when the heart was given 50 Hz stimulation,and the early after depolarization phenomenon was relieved under 6Hz stimulation.Conclusion:(1)In this study,a 128-channel pen electrode combined with Langendorff perfusion was used to record electrical signals in isolated SD rat hearts,and the ischemia-reperfusion model was successfully established.(2)Mongolian medicine Zandan-3 decoction has anti-myocardial ischemia-reperfusion injury-induced ventricular arrhythmia.The concentration of 1.25mg/ml,6.25mg/ml and12.5mg/ml all have a certain effect on cardiac conduction,and the concentration of 12.5mg/ml has a significant difference.(3)Zandan-3 decoction has antiarrhythmic effects by prolonging QRS,ERP,atrioventricular delay time and reducing ventricular rate. |
PDF Full Text Request