The sodium-hydrogen exchanger isoform-1 (NHE-1) is the predominant isoform of the Na+/H+ exchanger and is expressed in the heart where it contributes to cardiomyocyte pH homeostasis. It plays an important role in the myocardial response to ischemia-reperfusion. Cariporide is a benzoylguanidine compound that inhibits NHE-1 with IC50 values ranging from 0.03-3.4 μM. It displays selectivity for NHE-1 over NHE-2, NHE-3, and NHE-5 (IC50s = 4.3-62, 1->100, and >30 μM, respectively). The cardioprotective efficacy of cariporide has been examined in clinical investigations of patients at risk for myocardial infarction.
