Effects On Myocardiac Infarction Mice Q-T Interval And Myocardial Monophasic Action Potential After Induced Pluripotent Stem Cells Transplantation

[Objective]To study the effect of induced ploripotent stem cells's(ipS cells) transplantation on electrical activity of the mice heart and evaluate its safety and validity.[Methods]When acute myocardiac infarction (AMI) model mice named by American Institute of Cancer Research(ICR) was constructed successfully, They were divided into 4 groups randomly: AMI group,AMI + Normal saline group, AMI + ipS cells group, AMI + Fb (fibroblasts) grupe and the normal control group was set up at the same time.The changes of Q-T interval of the limb lead II surface ECG and regional myocardial monophasic action potential of every groups mice were checked by BL-420 organism function system at five minutes,one week,two weeks,and three weeks after ipS cells transplantation. The expression of connexin 43 in mice groups were checked by immunohistochemistry method, and half quality analysis was carry out through the soft ware of Image Proplus.[Results]At two weeks after transplantation,the Q-T interval of limb lead II surface ECG of the group of AMI+ipS was obviously shorted compared with other groups, and all had significant difference between two groups. The amplitude and the 50% of repolarization of action potential duration (MAPD50) of regional myocardial monophasic action potential of the AMI+ipS group had rebounded compared with other groups, but QRS time was significantly shorted compared with other groups,and all had significant difference between two groups.The expression of connexin 43 was obviously higher than the other groups in the result of immunohistochemistry.[Conclusions]First, induced pluripotent stem cells could be normally survival when transplanted in the host after three weeks, no cardiac tumors were founded; Second,although it could cause the premature ventricular contractions, no malignant arrhythmia such as ventricular tachycardia, ventricular fibrillation were observed; Moreover, the ipS cells transplantation can significantly improve the basic electrophysiological indicators, such as Q-T interval, regional myocardial monophasic action potential, while no such phenomenon discovered in fibroblasts;Finally, the ipS cells transplantation could accelerate the expression of connexin 43 in the areas of acute myocardial infarction in mice, which may had a certain relationship with no causing of malignant arrhythmia.