A Comparison ofAdenosine-Induced Cardioprotection andIschemic Preconditioning inDogs Efficacy, TimeCourse, andRoleofKATPChannels

Background Adenosine hasbeenproposed tobeanimportantmediator ofischemic preconditioning. Intracoronary administration ofadenosine hasrecently beenshowntomimic theeffects ofpreconditioning inisolated rabbit hearts. However, itisnotknownwhether this agentcanduplicate the effects ofpreconditioning invivo orinother species. Thus, the first objective ofthepresent study wastodetermine whether adenosine canlimit myocardial necrosis tothesameextent as preconditioning inanesthetized dogs. A second objective was todetermine whether theduration oftheadenosine-induced cardioprotection persisted aslong asthat ofischemic preconditioning. Finally, a third aimwastodetermine whether adenosine mediates its cardioprotection viatheKATchannel, which hasbeenshowntobeanimportant mediator ofpreconditioning inseveral animal species, including dogs. Methods andResults Barbital-anesthetized