Concentration-dependent wrestling between detrimental and protective effects of H2O2 during myocardial ischemia/reperfusion.

ABSTRACT: Reactive oxygen species (ROS) and endoplasmic reticulum (ER) stress are paradoxically implicated in myocardial ischemia/reperfusion (I/R) injury and cardioprotection. However, the precise interpretation for the dual roles of ROS and its relationship with the ER stress during I/R remain elusive. Here we investigated the concentration-dependent effects of hydrogen peroxide (H2O2) preconditioning (PC) and postconditioning (PoC) on the ER stress and prosurvival reperfusion injury salvage kinase (RISK) activation using an ex vivo rat myocardial I/R model. The effects of H2O2 PC and PoC showed three phases. At a low level (1 μM), H2O2 exacerbated I/R-induced left ventricular (LV) contractile dysfunction and ER stress, as indicated by enhanced phosphorylation of protein kinase-like ER kinase and

SUBMITTER: Wang ZH 

PROVIDER: S-EPMC4611739 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature