Exercise-Induced Myocardial Stunning And Its Energy Metabolism Disorders Mechanism Research

ObjectiveResearch myocardial stunning induced by high intensity exercise and its energy metabolism disorders mechanism of EIMS.MethodsExpⅠ:24 SD rats were divided into control group (A,n=8) and exercise group (B,n=14).According to the exercise reseal electrocardiogram,group B were divided into ECG abnormalities group (B1,n=8) and ECG normal group (B2,n=6),we determinated electrocardiogram and cardiac function at before exercise,after exercise 0,5,10,15,20,30,50,70,90 and 110min respectively,And analysis HE in 110min after exercise.ExpⅡ:24 SD rats were divided into control group(A,n=8),EIMS+H2O2(C,n=8)and EIMS+ATP(D,n=8),we determinated myocardial mitochondria ST3,ST4 and RCR, myocardial AMP content,ATP content,AMPK activity,M-CPT-I mRNA,MEF2a mRNA,MCAD mRNA,GLUT4 mRNA and PGC-1a,PPARa,GLUT4 protein.Results(1) High intensity exercise induced ECG reversibly abnormalities,performance for J spot value,T wave value changes.(2) LVESP and+dp/dtmax of group B1 appear twice lifting phenomenon after high intensity exercise,the second lifting change for myocardial stunning,group B2 has not seen the obviously second lifting changes.(3) Comparison between groups,HE dyeing non-significance difference.(4) Compared with group A,myocardial ATP content of group C dropped significantly,AMP content of group C,AMP/ATP of group C,AMPK-activity of group C,α-MHCmRNA of group C,α-MHCmRNA/β-MHCmRNA of group C,LVESP of group C all were significantly increased,M-CPT-ImRNA,MEF2a mRNA, GLUT4 mRNA MCAD mRNA,GLUT4 protein of group C all were significantly increased,FFA content of group C was lossed.Myocardial mitochondria PGC-1a,PPARa protein expression were increased.Compared with group C, group D(ATP supplement),myocardial ATP content of group D was very significant rise,AMP content non-significance difference, AMP/ATP,AMPK activity, MEF2a mRNA,GLUT4 mRNA,GLUT4 protein are significantly,a-MHC mRNA,a-MHC mRNA/β-MHC mRNA,LVESP,M-CPT-I mRNA,MCAD mRNA all were significantly increased;(3-MHC mRNA non-significance difference,FFA content was significantly reduced;Mitochondria PGC-1a,PPARa were significant.Conclusion(1) High intensity exercise can induce mayocardium stunned,performance characteristics:ECG abnormal,short-term reversible myocardial dysfunction and myocardial tissue dyeing does not change significantly,these characteristics were similared with clinical myocardial stunning performance characteristics.(2) Myocardial cell energy metabolization disorders is one of EIMS possible mechinisms,we can promote EIMS myocardial recovery via ATP supplement.