Objective We investigated the effects of pioglitazone on atrial ionic channel remodelling in alloxan-induced diabetic rabbits, and electrophysiological mechanisn of pioglitazone on atrial fibrillation.
Methods 32 rabbits were divided into CN group, DM group, DPG group and DPI group. Langendorff-perfused rabbit hearts were used to isolate single atrial myotcyte, and whole-cell patch-clamp technique was used to record action potential duration (AP) and atrial ionic channel currents (ICa, L and INa).
Results Compared with controls, APD90 and APD50 of left atrial myocytes were significantly prolonged in DM group (P < 0.05 vs. CN), and APD90 rate adaptation was no significant differences (P > 0.05 vs. CN). The densities of INa were reduced and the densities of ICa, L were increased in DM group (P < 0.01 vs. CN). The above were markly attenuated in DPG and DPI group.
Conclusions Pioglitazone may prevent atrial ionic channel remodelling in diabetic rabbits, even play an important prevention to DM-related AF.