Comparative Analysis of the Effects of Omeprazole and Ischemic Preconditioning in Protection against Ischemia and Reperfusion Myocardial: Experimental Study in Isolated Rat Hearts

Abstract

Introduction: Myocardial protection against ischemic injury has been a major focus of studies of cardiovascular sciences worldwide. In 1986, Murry et al. became pioneers by showing a special ischemic preconditioning technique in hearts of dogs which motivated researches for better understanding of endogenous protective mechanisms of the human heart. The aim of this study was to evaluate the effects of omeprazole on protection of functional recovery of isolated rat hearts subjected to ischemia-reperfusion with and without ischemic preconditioning (IP). Methods: In five groups of eight Wistar breed rats, the hearts were removed after anesthesia and perfused with Krebs-Henseleit solution (95% O 2 , 5% CO 2 , 37ºC). The GI was a control group. The GII, GIII, GIV and GV, hearts were submitted to ischemia (20 min) and reperfusion (30 min). In GIV and GV, preconditioning was performed with 5 min of ischemia and 5 min of reperfusion before 20 min of the ischemia period induction. In GIII and GV Omeprazole 200 µg was done before a 20 min-period of ischemia induction. Heart Rate (HR), Coronary Flow (CF), Systolic Pressure (SP), +dP/dt and−dP/dt were registered before (t0) and after reperfusion (t30). Kruskal-Wallisand Mann-Whitney (p<0.05) test were used. Results: The CF analysis showed that the Groups II, III, IV and V, had a similar behavior analyzed over time (p=0.316). Group I presented the averages 18.6, 17.5 and 16.6 at t0, t15' and t30' respectively, with significant changes in the pattern of behavior analyzed over time (p<0.001). There were no significant differences in the HR, SP, +dP/dt max , and −dP/dt max between Groups I, III, IV and V results. Conclusion: Omeprazole conferred preconditioning characteristics to isolated rat hearts subjected to ischemic injury. There was no greater efficacy of protection shown in relation to existing methods of ischemic preconditioning. There was no synergism in the use of omeprazole in conjunction with the methods of IP.