title: Effects of Kaempferia parviflora Wall. Ex. Baker on electrophysiology of the swine hearts.
abstract: OBJECTIVE
  Pre-clinical studies in swine have demonstrated that a supratherapeutic concentration of sildenafil citrate decreased defibrillation efficacy and facilitated cardiac arrhythmia. We therefore, decided to investigate the effects of Kaempferia parviflora (KP) extract on these parameters in the swine heart. The underlying assumption was that in the heart, KP might be producing effects similar to sildanafil citrate as KP has long been used in southeast Asian traditional medicine to correct erectile dysfunction.
  
  
  METHODS
  The study was conducted as the defibrillation study, and ventricular fibrillation (VF) induction study. In both studies, the defibrillation threshold (DFT), the upper limit of vulnerability (ULV) and VF threshold were determined before and after KP extract administration.
  
  
  RESULTS
  In both studies KP extract at high concentrations (100 and 50 mg/kg) significantly increased the DFT and ULV, without altering the VF threshold. At these concentrations, systolic and diastolic blood pressures were also attenuated.
  
  
  CONCLUSIONS
  High concentrations of KP extract attenuated defibrillation efficacy and increased cardiac vulnerability to arrhythmia in a normal swine heart. When used in appropriate concentrations, its blood pressure lowering effect may be useful in hypertensive states. Further studies need to be done to elucidate its mechanism of action.
authors.affiliation: Department of Physiology & Cardiac Electrophysiology Research & Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Punate
authors.initials: P
authors.lastname: Weerateerangkul
authors.forename: Sirirat
authors.initials: S
authors.lastname: Surinkaew
authors.forename: Siriporn C
authors.initials: SC
authors.lastname: Chattipakorn
authors.forename: Nipon
authors.initials: N
authors.lastname: Chattipakorn
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000188:drug therapy*; D001794:Blood Pressure / Q000187:drug effects; D004554:Electric Countershock; D055724:Electrophysiological Phenomena / Q000187:drug effects; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology; D006329:Heart Conduction System / Q000187:drug effects; D010879:Piperazines / Q000008:administration & dosage; D010936:Plant Extracts / Q000008:administration & dosage* / Q000737:chemistry; D011687:Purines / Q000008:administration & dosage; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000008:administration & dosage; D013552:Swine; D014693:Ventricular Fibrillation / Q000188:drug therapy* / Q000503:physiopathology; D030521:Zingiberaceae / Q000737:chemistry
chemical_list: D010879:Piperazines; D010936:Plant Extracts; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate