Effects of anandamide on potassium channels in rat ventricular myocytes: a suppression of Ito and augmentation of KATP channels
| Autor: | Sheng Li Song, Yi Zhang, Min Shi, De Pei Li, Hui Juan Ma, Qian Li, Hui Jie Ma |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Male
Indoles Patch-Clamp Techniques Polyunsaturated Alkamides Physiology Heart Ventricles Arachidonic Acids Pharmacology Rats Sprague-Dawley Receptor Cannabinoid CB2 chemistry.chemical_compound KATP Channels Piperidines Receptor Cannabinoid CB1 Animals Myocytes Cardiac Ventricular myocytes Receptor Dose-Response Relationship Drug Arrhythmias Cardiac Cell Biology Anandamide Endocannabinoid system Potassium channel Rats Electrophysiology chemistry Pyrazoles Cardiac Electrophysiology Anti-Arrhythmia Agents Endocannabinoids |
| Zdroj: | American Journal of Physiology-Cell Physiology. 302:C924-C930 |
| ISSN: | 1522-1563 0363-6143 |
| DOI: | 10.1152/ajpcell.00228.2011 |
| Popis: | Anandamide is an endocannabinoid that has antiarrhythmic effects through inhibition of L-type Ca2+ channels in cardiomyocytes. In this study, we investigated the electrophysiological effects of anandamide on K+ channels in rat ventricular myocytes. Whole cell patch-clamp technique was used to record K+ currents, including transient outward potassium current ( Ito), steady-state outward potassium current ( Iss), inward rectifier potassium current ( IK1), and ATP-sensitive potassium current ( IKATP) in isolated rat cardiac ventricular myocytes. Anandamide decreased Ito while increasing IKATP in a concentration-dependent manner but had no effect on Iss and IK1 in isolated ventricular myocytes. Furthermore, anandamide shifted steady-state inactivation curve of Ito to the left and shifted the recovery curve of Ito to the right. However, neither cannabinoid 1 (CB1) receptor antagonist AM251 nor CB2 receptor antagonist AM630 eliminated the inhibitory effect of anandamide on Ito. In addition, blockade of CB2 receptors, but not CB1 receptors, eliminated the augmentation effect of anandamide on IKATP. These data suggest that anandamide suppresses Ito through a non-CB1 and non-CB2 receptor-mediated pathway while augmenting IKATP through CB2 receptors in ventricular myocytes. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|