Department of Anesthesiology, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 167 Road Beilishi, Beijing, 100037, China.
Mol Biol Rep. 2010 Dec;37(8):3763-9. doi: 10.1007/s11033-010-0030-5. Epub 2010 Mar 10.
Volatile anesthetic ischemic postconditioning reduces infarct size following ischemia/reperfusion. Whether phosphorylation of protein kinase B (PKB/Akt) and glycogen synthase kinase 3 beta (GSK3β) is causal for cardioprotection by postconditioning is controversial. We therefore investigated the impact of PKB/Akt and GSK3β in isolated perfused rat hearts subjected to 40 min of ischemia followed by 1 h of reperfusion. 2.0% sevoflurane (1.0 minimum alveolar concentration) was administered at the onset of reperfusion in 15 min as postconditioning. Western blot analysis was used to determine phosphorylation of PKB/Akt and its downstream target GSK3β after 1 h of reperfusion. Mitochondrial and cytosolic content of cytochrome C checked by western blot served as a marker for mitochondrial permeability transition pore opening. Sevoflurane postconditioning significantly improved functional cardiac recovery and decreased infarct size in isolated rat hearts. Compared with unprotected hearts, sevoflurane postconditioning-induced phosphorylation of PKB/Akt and GSK3β were significantly increased. Increase of cytochrome C in mitochondria and decrease of it in cytosol is significant when compared with unprotected ones which have reversal effects on cytochrome C. The current study presents evidence that sevoflurane-induced cardioprotection at the onset of reperfusion are partly through activation of PKB/Akt and GSK3β.
挥发性麻醉药缺血后处理可减少缺血/再灌注后的梗死面积。蛋白激酶 B(PKB/Akt)和糖原合成酶激酶 3β(GSK3β)的磷酸化是否是后处理引起心脏保护的原因存在争议。因此,我们研究了 PKB/Akt 和 GSK3β 在经历 40 分钟缺血和 1 小时再灌注的分离灌注大鼠心脏中的作用。再灌注开始时给予 2.0%七氟醚(1.0 最低肺泡浓度)作为后处理,持续 15 分钟。再灌注 1 小时后通过 Western blot 分析确定 PKB/Akt 及其下游靶标 GSK3β的磷酸化。通过 Western blot 检测细胞色素 C 的线粒体和胞质内容物作为线粒体通透性转换孔(MPTP)开放的标志物。七氟醚后处理显著改善了分离大鼠心脏的功能恢复并减少了梗死面积。与未保护的心脏相比,七氟醚后处理诱导的 PKB/Akt 和 GSK3β 磷酸化显著增加。与未保护的心脏相比,线粒体中细胞色素 C 的增加和胞质中细胞色素 C 的减少是显著的,这对细胞色素 C 具有逆转作用。本研究提供的证据表明,再灌注开始时七氟醚诱导的心脏保护部分是通过激活 PKB/Akt 和 GSK3β 实现的。