The effect of sevoflurane postconditioning on cardioprotection against ischemia-reperfusion injury in rabbits.

Sevoflurane postconditioning is a potential clinical measure to protect myocardial. This experiment was designed to investigate the efficacy of sevoflurane postconditioning against ischemia-reperfusion injury. A total of 132 Japanese White Rabbits were enrolled into this study. They were underwent 15-, 30-, or 60-min left anterior descending coronary (LAD) artery occlusion, respectively. At the end of LAD artery occlusion, they randomly received a 5-min inhalation of air (control group), 1% sevoflurane (1% sev group), 2% sevoflurane (2% sev group), 4% sevoflurane (4% sev group) or an IV bolus injection of 5 mg/kg of NIM811 [a specific inhibitor of mitochondrial permeability transition pores (mPTP)]. Infarct size was determined after 2 h of reperfusion (triphenyltetrazolium chloride straining, percentage of risk area). The infarct sizes were significantly (P < 0.05) reduced after 15 min ischemia (5.5 ± 3.3%, 5.8 ± 3.6% vs. 20.3 ± 6.9% for 2% sev, 4% sev vs. control, respectively) and 30 min ischemia (23.5 ± 5.0%, 20.7 ± 5.9% vs. 50.9 ± 10.2%, for 2% sev, 4% sev vs. control, respectively; P < 0.05). However, it had no effect on infarct size after 60 min ischemia (64.1 ± 5.9%, 62.3 ± 7.6% vs. 72.7 ± 9.2% for 2% sev, 4% sev vs. control, respectively, P > 0.05).The efficacy of sevoflurane postconditioning gradually weakened with increasing ischemia duration and disappears after 60 min ischemia in rabbits in vivo.