The protective effect of fasudil pretreatment combined with ischemia postconditioning on myocardial ischemia/reperfusion injury in rats

OBJECTIVE: Ischemic postcondi - tioning (IPO) and pharmacological pretreatment may reduce myocardial necrosis and apoptosis during ischemia/reperfusion. This study aimed to determine the protective effect of fasudil pretreat - ment combined with IPO on myocardial is - chemia/reperfusion injury in rats and explore the possible mechanism s. MATERIALS AND METHODS: The SD rats were induced by intraperitoneal injection of fa - sudil hydrochloride (1 or 10 mg/kg) 60 min be - fore the initiation of ischemia, while the control rats were given the same volume of saline. The hearts were hung on the Langendorff perfusion apparatus and underwent 30 min global is - chemia and 120 min reperfusion. The IPO proto - col was induced by six cycles of 10 sec ischemia and 10 sec reperfusion at the onset of reperfu - sion. The hemodynamic changes were mea - sured, myocardial infarct size was determined by triphenyltetrazolium chloride (TTC) staining, car - diomyocyte apoptosis was detected by TUNEL staining, lactate dehydrogenase (LDH) was ana - lyzed from coronary effluents, phosphorylation of Akt and eNOS, as well as expression of Bcl-2 and Bax were measured by western blotting analysis. RESULTS: The high-dose fasudil (10 mg/kg) pretreatment group and IPO group significantly improved post-ischemia cardiac function, re - duced myocardial infarct size, attenuated car - diomyocyte apoptosis, decreased the release of LDH, increased expression of phospho-Akt, phospho-eNOS and Bcl-2, and reduced expres - sion of Bax compared with the control group ( p < 0.05). In addition, the high-dose fasudil pre - treatment combined with IPO group could fur - ther improved post-ischemia cardiac function, reduced myocardial infarct size, attenuated car - diomyocyte apoptosis, decreased the release of LDH, increased expression of phospho-Akt, phospho-eNOS and Bcl-2, and reduced expres - sion of Bax compared with the single treatment groups ( p < 0.05). CONCLUSIONS: The combination of high-dose fasudil pretreatment and IPO had a synergistic