Diabetes mellitus (DM) increases the risk of developing atrial fibrillation (AF), but the molecular mechanisms of diabetes-induced atrial remodeling processes have not been fully characterized. The aim of this study was to examine the mechanisms underlying atrial ion channel remodeling in alloxan-induced diabetes model in rabbits. A total of 40 Japanese rabbits were randomly assigned to a control group (C), alloxan-induced diabetic group (DM), probucol-treated control group (Control-P), and probucol-treated diabetic group (DM-P). Using whole-cell voltage-clamp techniques, ICa,L, INa and action potential durations (APDs) were measured in cardiomyocytes isolated from the left atria in the four groups, respectively. In the DM group, increased Ica,L and decreased INa currents were reflected in prolonged APD90 and APD50 values. These changes were reversed in the DM-P group. In conclusion, probucol cured AF by alleviating the ion channel remodeling of atrial myocytes in the setting of diabetes and the promising therapeutic potential of anti-oxidative compounds in the treatment of AF warrants further study.
Keywords: Pathology Section; alloxan-induced diabetes; atrial fibrillation; atrial ionic remodeling; calcium current; diabetes mellitus.