Study design and protocols.

<p>Two protocols were designed in this study, namely, 1) mechanistic study and 2) I/R model. In mechanistic protocol, various receptors antagonists were pretreated 15 min before remote electro-stimulation (RES). In I/R model, various receptors antagonists were pretreated 15 min before RES preconditioning, followed by 1h-ischemia and 3 h-reperfusion.