Abstract:

[Objective] This paper attempts to investigate whether sigma-1 receptor (Sig1R) activation attenuate myocardial ischemia reperfusion injury (MIRI) and whether Sig1R inhibition exacerbates MIRI in mice model. [Methods] C57BL/6 mice are injected via tail vein with BD1047 (Sig1R inhibitor), SA4503 (Sig1R activator) or saline 3 days before MIRI surgery. Then, double-staining technique and western blot analysis are performed on myocardium tissue. [Results] Mice that have received BD1047 pretreatment demonstrate a significant increase in the myocardial infarction size after I/R compared with control group ($P\!\!<$0.05), and a significantly increased expression of Bax and Caspases-3 proteins and a significantly reduced expression of Bcl-2 protein compared with sham control, MIRI control and sham BD1047 groups ($P\!<$0.05). Mice that have received SA4503 pretreatment demonstrate a significant reduction in myocardial infarction size after I/R compared with control group ($P\!<$0.05), and a significantly reduced expression of Bax and cleaved Caspases-3 proteins and a significantly increased expression of Bcl-2 protein compared with sham control, MIRI control and sham SA4503 groups ($P\!<$0.05). [Conclusions] SA4503 protects MIRI and reduces myocardial infarction whereas BD1047 deteriorates MIRI and augment myocardial infarction, and these effects may be achieved through activation or inhibition of Sig1R.

Key words: Sigma-1 receptor, mycardial infarction, ischemia reperfusion injury