ABSTRACT
Ischemic heart disease remains a leading cause of morbidity and mortality. The present study aimed at investigating the cardio protective effect of pharmacologic preconditioning with dipyridamole, an adenosine uptake inhibitor, on the variable facets produced by ischemia/reperfusion in isolated rat hearts previously stressed by isoproterenol infusion. Hearts were preconditioned by injecting rats i.p. with 4mgkg dipyridamole twice a day, 6 days / week, for 4 weeks. The control group received i.p injection of saline in a volume equivalent to that used to dissolve the drug. Isolated rat hearts were perfused for 3 min with isoproterenol, followed by 30 min of global ischemia and then 30 min of reperfusion. On exposing the heart to the stress of isoproterenol infusion followed by ischemia reperfusion insult, dipyridamole 1 was capable of improving recovery of cardiac muscle and decreasing the infarct size as compared with the control group. This could be explained by the present findings that dipyridamole preconditioning stimulated myocardial angiogenesis with marked increment in mitochondria1 number and size, and significantly de- creased MDA level to an extent that could be sufficient to exert significant cardio protection due to enhanced ventricular contractile functional reserve at pre-ischemic stag