Protective effect of piperine on electrophysiology abnormalities of left atrial myocytes induced by hydrogen peroxide in rabbits

Abstract Aims Piperine had protective effects on oxidative stress damage of ventricular myocytes by hydrogen peroxide (H 2 O 2 ). In this study we aimed to explore the protective effect of piperine on abnormalities of the cardiac action potential (AP) and several ion currents induced by hydrogen peroxide (H 2 O 2 ) in single rabbit left atrial myocyte. Main methods Conventional microelectrodes were used to record action potential duration (APD), resting membrane potential (RMP) and some ion currents (I Ca,L ,I to ,I K1 and I kur ,ect.), before and after H 2 O 2 administration with or without piperine. Key findings The piperine (7 μmol/L) had no significant effect on APD, I Ca,L ,I to ,I K1 and I kur and their channel dynamics. In the presence of 50 μmol/L H 2 O 2 , APD 50 and APD 90 shortened ( P P Ca,L reduced significantly ( P 2 O 2 on APD and I Ca,L ( P Ca,L dynamics induced by H 2 O 2 . The peak current of I to was reduced significantly ( P 2 O 2 on I to ( P to dynamics induced by H 2 O 2. The peak current of I K1 and I KUr was significantly reduced ( P 2 O 2 on I K1 and I KUr significantly ( P KUr dynamics induced by H 2 O 2 . Significance These results suggest that piperine effectively protects atrial myocytes from oxidative stress injury in atrial electrophysiology.