Effects of piperine on abnormalities of inward rectifier potassium current and ultra rapid delayed rectifier potassium current induced by hydrogen peroxide in rabbit atrial myocytes |
| |
Authors: | LIU Yan LI Yang LIN Kun TIAN Miao WANG Yu-tang SHAN Zhao-liang |
| |
Institution: | 1. Department of Cardiology, Chinese PLA General Hospital, Beijing 100853, China;2. Institute of Geriatric Cardiology, Chinese PLA General Hospital, Beijing 100853, China |
| |
Abstract: | AIM: To study the protective effect of piperine on abnormalityies of inward rectifier potassium current (IK1) and ultra rapid delayed rectifier potassium current (IKUr) induced by hydrogen peroxide (H2O2) in single rabbit atrial myocytes. METHODS: The technique of whole-cell patch-clamp was used to study the effect of H2O2 at concentration of 50 μmol/L on IK1 and IKUr in single rabbit atrial myocytes. The protective effect of pretreatment with piperine (7 μmol/L) was also observed. RESULTS: The piperine at concentration of 7 μmol/L had no significant effect on IK1 and IKUr and their channel dynamics. In the presence of H2O2 at concentration of 50 μmol/L, the peak currents of IK1 and IKUr reduced significantly (P<0.05).The steady-state activation curve of IKUr was shifted right, the steady-state inactivation curve of IKUr was shifted left, and the recovery from inactivation of IKUr was shifted downward. The IKUr showed frequency-dependent characteristics. Piperine at concentration of 7 μmol/L significantly alleviated the inhibitory effect of H2O2 on IK1 and IKUr (P<0.01). In addition, piperine protected against the changes of IKUr dynamics induced by H2O2. CONCLUSION: Piperine alleviates the abnormalities of IK1 and IKUr induced by oxidative stress in atrial myocytes. |
| |
Keywords: | Piperine Hydrogen peroxide Atrial myocytes Inward rectifier potassium current Ultra rapid delayed rectifier potassium current |
|
| 点击此处可从《园艺学报》浏览原始摘要信息 |
| 点击此处可从《园艺学报》下载免费的PDF全文 |
|