Effect of Gingkgo biloba leaf extract induced delayed preconditioning on cytochrome c oxidase expression during myocardial ischemia-reperfusion in rats

To determine the effect of Gingkgo biloba leaf extract (EGb761) induced delayed preconditioning on cytochrome c oxidase (CcO) expression during myocardial ischemia-reperfusion in rats. Four groups (10 in each) of Sprague-Dawley male rats were studied. In the sham group, the rats received no treatment. Rats in the ischemia-reperfusion (IR) group were treated with NS (1.0 mL/kg intravenously) 24 h before ischemia. Rats in the M group were treated with EGb761 (100 mg/kg intravenously) 24 h before the ischemia. In the D group , EGb761-treated rats that received the 5-hydroxydecanoate (5-HD), an inhibitor of mitochondrial KATP channels 15 min before the ischemia. The IR, M, and D groups were subjected to ischemia by 30 min of coronary artery occlusion before 2 h of reperfusion. At the end of the reperfusion, myocardial infarct size was measured. CcO was measured by Western blot. The myocardial ultrastructure was observed under the electron microscope. The infarct size was significantly smaller in the M group [(23.