Abstract:Objective:To study whether sodium-hydrogen exchange inhibitor(NHEI)can enhance the protective effect of hyperpolarized preservation solution containing potassium channel opener (PCO),and the effect was compared with that of Celsior solution.Methods: After equilibrated on a crystalloid-perfused Langendorff model for 30 min,rabbit hearts were divided into four groups:(1) Cel group:receiving another 30 min of equilibration,8 h cold storage with Celsior solution and 1 h reperfusion; (2) Pin group:arrested and stored with pinacidil (a type of PCO) hyperpolarizing cardioplegia; (3) Cel+Car group:receiving the same treatment as Cel group except that 10 μmol/L cariporide (a type of NHEI) was administered during the second equilibration period and reperfusion; and (4) Pin+Car group:receiving cariporide treatment and hyperpolarized arrest and storage.Results: Recovery rate of systolic function in the Pin+Car group was significantly higher than that in the Pin group (\[87.4±11.9\]% vs \[69.0±7.2\]%,P<0.05) and comparable to that in the Cel group (\[93.4±5.2\]%,P>0.05 ).No significant differences were found in any parameters between Cel group and Cel+Car group.There were no differences in coronary flow among all groups.Conclusion: NHEI can greatly enhance the protective effect of PCO hperpolarized preservation solution on the donor heart,and the combination of them has a comparable protective effect to Celsior solution.