title: The effect of Korean red ginseng extract on the relaxation response in isolated rabbit vaginal tissue and its mechanism.
abstract: BACKGROUND
  Ginseng is an herbal medicine with a variety of biological activities.
  
  
  OBJECTIVE
  The purpose of this study was to investigate the effect of Korean red ginseng (KRG) extract on the relaxation response in isolated rabbit vaginal tissue and its mechanism as a potential therapeutic agent for female sexual dysfunction.
  
  
  METHODS
  Strips of rabbit vagina were mounted in organ chambers to measure isometric tension. After the strips were precontracted with phenylephrine, the contractile responses to KRG extract (1-20 mg/mL), nitric oxide inhibitor (N[omega]-nitro-L-arginine methyl ester [L-NAME]), an inhibitor of soluble guanylate cyclase (methylene blue), an inhibitor of Ca(2+)-activated K(+) channels (tetraethylammonium [TEA]), and an adenosine triphosphate (ATP)-sensitive K(+) channel blocker (glybenclamide) were examined.
  
  
  METHODS
  The relaxation of the vaginal tissue strip was assessed after treating KRG extract or other chemicals.
  
  
  RESULTS
  KRG (1-20 mg/mL) extract relaxed the vaginal tissue strip in a dose-dependent manner up to 85%. The relaxation effect was significantly inhibited by L-NAME (30 microM) and methylene blue (30 microM) (P < 0.05). In addition, KRG inhibited the contraction induced by depolarization with 10, 20, and 40 mM KCl. The KRG-induced relaxation effect was significantly inhibited by TEA (300 microM) (P < 0.05), and not by glybenclamide (30 microM).
  
  
  CONCLUSIONS
  These data show that KRG extract has a relaxing effect on rabbit vaginal smooth muscle tissue. These effects might be mediated partly through the NO pathway and hyperpolarization via Ca(2+)-activated K(+) channels.
authors.affiliation: Department of Urology, Chonnam National University Medical School, Gwangju, Korea.
authors.forename: Sun-Ouck
authors.initials: SO
authors.lastname: Kim
authors.forename: Min Kyung
authors.initials: MK
authors.lastname: Kim
authors.forename: Hyun-Suk
authors.initials: HS
authors.lastname: Lee
authors.forename: Jong Kwan
authors.initials: JK
authors.lastname: Park
authors.forename: Kwangsung
authors.initials: K
authors.lastname: Park
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D006162:Guanylate Cyclase / Q000502:physiology; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D009569:Nitric Oxide / Q000502:physiology; D005894:Panax; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D024681:Potassium Channels, Calcium-Activated / Q000187:drug effects / Q000502:physiology; D011817:Rabbits; D014621:Vagina / Q000187:drug effects*
chemical_list: D010936:Plant Extracts; D024681:Potassium Channels, Calcium-Activated; D009569:Nitric Oxide; D006162:Guanylate Cyclase