title: Antinociceptive effects, acute toxicity and chemical composition of Vitex agnus-castus essential oil.
abstract: OBJECTIVE
  Vitex agnus-castus (VAC) and its essential oil have been traditionally used to treat many conditions and symptoms such as premenstrual problems, mastalgia, inflammation, sexual dysfunction, and pain. In this study, the effects of essential oil extracted from Vitex agnus-castus (EOVAC) leaves were investigated in three behavioral models of nociception in adult male Wistar rats.
  
  
  METHODS
  Chemical composition of EOVAC was analyzed using gas chromatography - mass spectrometry (GC-MS) and also its possible toxicity was determined in mice. Analgesic effect of EOVAC was determined using tail immersion test, formalin test, and acetic acid-induced visceral pain in rats.
  
  
  RESULTS
  EOVAC (s.c.) and morphine (i.p.) significantly (p<0.05) reduced pain responses in both formalin and tail immersion tests. In the study of evolved mechanisms, pretreatment with naloxone or atropine significantly (p <0.05) reversed the essential oil-induced analgesia in both formalin and tail immersion tests. Moreover, EOVAC and Piroxicam produced significant (p<0.05) inhibition in the acetic acid-induced writhing response. EOVAC did not show any mortality even at high dose (5 g/kg, p.o.) of administration in toxicity test. Moreover, according to GC-MS results, major components of the EOVAC were α-pinene (14.83%), limonene (10.29%), β-caryophyllene (6.9%), sabinene (5.27%), and β-farnesene (5.9%).
  
  
  CONCLUSIONS
  These results suggest that endogenous opioidergic system as well as muscarinergic receptors of cholinergic system may be involve in the antinociceptive activity of Vitex agnus-castus essential oil in these models of pain in rats.
authors.affiliation: Division of Physiology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Emad
authors.initials: E
authors.lastname: Khalilzadeh
authors.affiliation: Division of Physiology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Vafaei Saiah
authors.affiliation: Division of Physiology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Hamideh
authors.initials: H
authors.lastname: Hasannejad
authors.affiliation: Division of Physiology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Adel
authors.initials: A
authors.lastname: Ghaderi
authors.affiliation: Division of Physiology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Shahla
authors.initials: S
authors.lastname: Ghaderi
authors.affiliation: Division of Histology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Hamidian
authors.affiliation: Department of Food Hygiene and Aquatics, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Razzagh
authors.initials: R
authors.lastname: Mahmoudi
authors.affiliation: Division of Physiology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Davoud
authors.initials: D
authors.lastname: Eshgi
authors.affiliation: Division of Physiology, Department of Basic Science, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, I.R.Iran.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Zangisheh
keywords: Acute toxicity; Chemical composition; Rat; Vitex agnus-castus Antinociception