title: Artemisinin blocks activating and slowly activating K+ current in guinea pig ventricular myocytes.
abstract: OBJECTIVE
  To study the effect of artemisinin (Art) on outward rectifier potassium current in ventricular myocytes.
  
  
  METHODS
  In isolated guinea pig ventricular myocytes, the effects of Art on the two components of delayed outward rectifier K+ current (IK), the rapidly activating inward K+ current (IKr), and the slowly rectifying outward K+ current (IKs) were observed by the whole cell patch-clamp technique.
  
  
  RESULTS
  Art decreased IK in a concentration-dependent manner. The IKstep and IKtail were reduced from 387 +/- 46 pA to 240 +/- 48 pA and from 299 +/- 30 pA to 130 +/- 38 pA, respectively at holding potential of +40 mV by Art 50 mumol.L-1. The envelope of tail analysis suggested that both IKr and IKs were inhibited.
  
  
  CONCLUSIONS
  Art blocked the two components of delayed outward rectifier K+ current (IKr and IKs) in guinea pig ventricular cells.
authors.affiliation: Department of Pharmacology, Harbin Medical University, China. Yangbf@Ems.hrbmu.edu.cn
authors.forename: B F
authors.initials: BF
authors.lastname: Yang
authors.forename: D L
authors.initials: DL
authors.lastname: Luo
authors.forename: L H
authors.initials: LH
authors.lastname: Bao
authors.forename: Y C
authors.initials: YC
authors.lastname: Zhang
authors.forename: H Z
authors.initials: HZ
authors.lastname: Wang
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D037621:Artemisinins; D002478:Cells, Cultured; D005260:Female; D006168:Guinea Pigs; D006352:Heart Ventricles / Q000166:cytology; D008297:Male; D009206:Myocardium / Q000166:cytology*; D015221:Potassium Channels / Q000187:drug effects*; D012717:Sesquiterpenes / Q000494:pharmacology*
chemical_list: D000889:Anti-Arrhythmia Agents; D037621:Artemisinins; D015221:Potassium Channels; D012717:Sesquiterpenes; C031327:artemisinin