The role of different opioid receptors subtype affecting mortality in preconditioned remote electro-stimulation (RES)-induced myocardial protection against ischemia/reperfusion (I/R) injury.

<p>In the I/R model, animals were randomly allocated into 6 groups as described in Methods. They were 1) sham RES group (n = 24); 2) RES preconditioning group (n = 20); 3) RES preconditioning pretreated with KOR blocker (n = 18); 4) RES preconditioning pretreated with DOR blocker (n = 10); 5) RES preconditioning pretreated with KOR/MOR antagonists, which left DOR active (n = 11); 6) RES preconditioning pretreated with DOR/MOR antagonists, which left KOR active (n = 9). The mortality rate (A), duration of tachyarrhythmia (B), CK-MB (C) and troponin I (D) were evaluated during I/R injury. Data are presented as mean ± S.E.M and were analyzed using repeated one-way analysis of variance (ANOVA) followed by the Dunnet’s test. Mortality rate was analyzed using Fisher’s exact test. A <i>p</i> value less than 0.05 is considered statistically significant. *, <i>p</i><0.05, <i>vs</i>. sham RES; #, <i>p</i><0.05, <i>vs</i>. RES. KOR, kappa opioid receptor; DOR, delta opioid receptor; MOR, mu opioid receptor. KOR left, KOR activity remained; DOR left, DOR activity remained; MOR left, MOR activity remained.