Inhibition of the Na⁺/H⁺Exchanger Confers Greater Cardioprotection Against 90 Minutes of Myocardial Ischemia Than Ischemic Preconditioning in Dogs

Abstract

These data demonstrate that although IPC and NHE-1 inhibition provide comparable protection against 60 minutes of myocardial ischemia, NHE-1 inhibition is more efficacious than IPC at protecting against a 90-minute ischemic insult. Furthermore, the combination of NHE-1 inhibition and IPC produces a greater-than-additive reduction in IS/AAR, suggesting either that NHE activity limits the efficacy of IPC or that different mechanisms are involved in the cardioprotective effect of IPC and NHE-1 inhibition.