Opioids and protection against ischemia-reperfusion injury: from experimental data to potential clinical applications.

Ischemic preconditioning, first demonstrated in animal myocardium, is an intrinsic and ubiquitous mechanism of marked protection against ischemia. Accumulating evidences have established that endogenous opioid peptides and their receptors play an important role in this adaptive phenomenon in the heart and other major organs. Of interest for therapeutic developments, opioid receptor agonists have been administered successfully to improve tolerance against experimental ischemia-reperfusion in various tissues. Recent human studies now raise the possibility to exploit this opioid-induced protection in clinical cardiac ischemia. These remarkable anti-ischemic properties of opioids and their emerging potential for organ protection in perioperative medicine will be reviewed at the light of pertinent results from basic and clinical researches.