José Gustavo Padrão Tavares1, Paolo Ruggero Errante2, Tânia Carmem Peñaranda Govato3, Ênio Rodrigues Vasques4, Renato Ribeiro Nogueira Ferraz5, Murched Omar Taha6, Francisco Sandro Menezes-Rodrigues7, Afonso Caricati-Neto8. 1. Fellow PhD degree, Postgraduate Program in Pharmacology, Universidade Federal de São Paulo (UNIFESP), Brazil. Conception and design of the study, analysis and interpretation of data, manuscript writing. 2. Fellow PhD degree, Postgraduate Program in Pharmacology, UNIFESP, Sao Paulo-SP, Brazil. Analysis and interpretation of data, manuscript writing. 3. Assistant Professor, Department of Pharmacology, Faculdade de Medicina do ABC (FMABC), Santo Andre-SP, Brazil. Statistical analysis. 4. Fellow PhD degree, Department of Gastroenterology, Faculty of Medicine, Universidade de São Paulo (USP), Brazil. Interpretation of electrocardiogram. 5. Full Professor, Program in Management of Health System (PMPA-GSS), Universidade Nove de Julho (UNINOVE), Sao Paulo-SP, Brazil. Critical revision. 6. Associate Professor, Department of Surgery, UNIFESP, Sao Paulo-SP, Brazil. Technical procedures. 7. Fellow PhD degree, Postgraduate Program in Pharmacology, UNIFESP, Sao Paulo-SP, Brazil. Critical revision. 8. Associate Professor, Department of Pharmacology, UNIFESP, Sao Paulo-SP, Brazil. Conception and design of the study, critical revision.
Abstract
PURPOSE: To investigate the cardioprotective effects of ischemic preconditioning (preIC) and postconditioning (postIC) in animal model of cardiac ischemia/reperfusion. METHODS: Adult rats were submitted to protocol of cardiac ischemia/reperfusion (I/R) and randomized into three experimental groups: cardiac I/R (n=33), preCI + cardiac I/R (n=7) and postCI + cardiac I/R (n=8). After this I/R protocol, the incidence of ventricular arrhythmia (VA), atrioventricular block (AVB) and lethality (LET) was evaluated using the electrocardiogram (ECG) analysis. RESULTS: After reestablishment of coronary blood flow, we observed variations of the ECG trace with increased incidence of ventricular arrhythmia (VA) (85%), atrioventricular block (AVB) (79%), and increase of lethality (70%) in cardiac I/R group. The comparison between I/R + preIC group with I/R group demonstrated significant reduction in VA incidence to 28%, AVB to 0% and lethality to 14%. The comparison of I/R + postIC group with I/R group was observed significance reduction in AVB incidence to 25% and lethality to 25%. CONCLUSION: The preconditioning strategies produce cardioprotection more efficient that postconditioning against myocardial dysfunctions and lethality by cardiac ischemia and reperfusion.
PURPOSE: To investigate the cardioprotective effects of ischemic preconditioning (preIC) and postconditioning (postIC) in animal model of cardiac ischemia/reperfusion. METHODS: Adult rats were submitted to protocol of cardiac ischemia/reperfusion (I/R) and randomized into three experimental groups: cardiac I/R (n=33), preCI + cardiac I/R (n=7) and postCI + cardiac I/R (n=8). After this I/R protocol, the incidence of ventricular arrhythmia (VA), atrioventricular block (AVB) and lethality (LET) was evaluated using the electrocardiogram (ECG) analysis. RESULTS: After reestablishment of coronary blood flow, we observed variations of the ECG trace with increased incidence of ventricular arrhythmia (VA) (85%), atrioventricular block (AVB) (79%), and increase of lethality (70%) in cardiac I/R group. The comparison between I/R + preIC group with I/R group demonstrated significant reduction in VA incidence to 28%, AVB to 0% and lethality to 14%. The comparison of I/R + postIC group with I/R group was observed significance reduction in AVB incidence to 25% and lethality to 25%. CONCLUSION: The preconditioning strategies produce cardioprotection more efficient that postconditioning against myocardial dysfunctions and lethality by cardiac ischemia and reperfusion.