title: Pharmacological characteristics of Artemisia vulgaris L. in isolated porcine basilar artery.
abstract: BACKGROUND
  In Vietnamese traditional herbalism, there are conflicting opinions about the effect of Artemisia vulgaris L. (AVL, English name: mugwort) on hypertension. Some ethnic doctors recommend the use of AVL for treatment of hypertension, whereas others advise against it. The purpose of this study was to clarify the pharmacological characteristics of AVL in isolated arteries to explain the conflicts surrounding the use of AVL for treatment of hypertension.
  
  
  METHODS
  We initially performed a functional study using an organ bath system to investigate the effect of AVL extract on isolated porcine basilar artery. We then measured the change in intracellular free Ca(2+) concentration elicited by AVL using cultured smooth muscle cells loaded with the Ca(2+) indicator fluo-4. Finally, using HPLC, we determined the active components in AVL.
  
  
  CONCLUSIONS
  AVL induced vasoconstriction at resting tension, and endothelial removal enhanced this effect significantly. Pretreatment with PD123319 (an AT2 receptor antagonist), Nω-nitro-L-arginine (a nitric oxide synthase inhibitor), or both, also enhanced this effect. AVL-induced contraction was competitively inhibited by methiothepin (a 5-HT1 and 5-HT2 receptor antagonist) in the presence of ketanserin (a 5-HT2 receptor antagonist). Removal of extracellular calcium with nifedipine (an L-type Ca(2+) channel blocker) or ruthenium red (a ryanodine receptor blocker) significantly reduced AVL-induced contraction, whereas losartan (an AT1 receptor antagonist) and diphenhydramine (a H1 receptor antagonist) had no effect on this contraction. AVL increased the intracellular free Ca(2+) concentration in cultured cells, and this increment was inhibited by methiothepin. HPLC analysis revealed that the retention time of the first peak in the AVL profile was similar to that of the 5-HT standard, and that addition of 5-HT to the AVL sample enhanced this peak. On the other hand, AVL induced endothelium-independent relaxation under precontracted conditions with 60mM KCl. Captopril (an angiotensin converting enzyme inhibitor), atenolol (a β1 receptor antagonist) and cimetidine (a H2 receptor antagonist) had no effect on this relaxation. In Ca(2+)-free 60mM KCl-containing solution, pretreatment with AVL significantly inhibited CaCl2-induced contraction.
  
  
  CONCLUSIONS
  For the first time, the present study has demonstrated that AVL has two opposite effects, contraction and relaxation, on isolated artery, which may help to explain the conflicting indications for AVL in traditional herbalism. 5-HT is a significant factor affecting artery contraction in the presence of AVL.
authors.affiliation: Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Ha Thi Thanh
authors.initials: HT
authors.lastname: Nguyen
authors.affiliation: Department of Plant Bio-technology, Faculty of Biotechnology, Vietnam National University of Agriculture, Trau Quy crossing, Gia Lam district, Hanoi, Vietnam.
authors.forename: Hai Thanh
authors.initials: HT
authors.lastname: Nguyen
authors.affiliation: Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Md Zahorul
authors.initials: MZ
authors.lastname: Islam
authors.affiliation: Department of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Obi
authors.affiliation: Department of Food Science and Technology, Faculty of Agro-Industry, Kasetsart University, Bangkok, Thailand.
authors.forename: Pitchaya
authors.initials: P
authors.lastname: Pothinuch
authors.affiliation: Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Phyu Phyu Khine
authors.initials: PP
authors.lastname: Zar
authors.affiliation: Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: De Xing
authors.initials: de X
authors.lastname: Hou
authors.affiliation: Department of Veterinary Surgery and Reproduction, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Trau Quy crossing, Gia Lam district, Hanoi, Vietnam.
authors.forename: Thanh
authors.initials: T
authors.lastname: Van Nguyen
authors.affiliation: Department of Internal Medicine and Pharmacology, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Trau Quy crossing, Gia Lam district, Hanoi, Vietnam.
authors.forename: Tuong Manh
authors.initials: TM
authors.lastname: Nguyen
authors.affiliation: Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Cuong
authors.initials: C
authors.lastname: Van Dao
authors.affiliation: Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Mitsuya
authors.initials: M
authors.lastname: Shiraishi
authors.affiliation: Department of Veterinary Pharmacology, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan. Electronic address: k1330977@kadai.jp.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Miyamoto
mesh_terms: D000818:Animals; D019306:Artemisia; D001488:Basilar Artery / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D005260:Female; D006973:Hypertension / Q000188:drug therapy; D066298:In Vitro Techniques; D008297:Male; D008519:Medicine, Traditional; D008719:Methiothepin / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves; D011189:Potassium Chloride / Q000494:pharmacology; D012701:Serotonin / Q000378:metabolism; D012702:Serotonin Antagonists / Q000494:pharmacology; D013552:Swine; D014661:Vasoconstriction / Q000187:drug effects; D014744:Vietnam
chemical_list: D010936:Plant Extracts; D012702:Serotonin Antagonists; D012701:Serotonin; D008719:Methiothepin; D011189:Potassium Chloride
keywords: Artemisia vulgaris L.; Basilar artery; Biphasic effects; Hypertension; Mugwort; Serotonin