title: Vitex Agnus Castus Extract Improves Learning and Memory and Increases the Transcription of Estrogen Receptor α in Hippocampus of Ovariectomized Rats.
abstract: BACKGROUND
  Lower level of estrogen hormone is considered as an important factor for loss of learning and memory in postmenopausal women. Although estrogen replacement therapy is used for compensation, but long-term usage of estrogen is associated with a higher risk of hormone-dependent cancers. Phytoestrogens, due to fewer side effects, have been proposed to prevent menopause-related cognitive decline.
  
  
  METHODS
  24 female Wistar rats weighing 180-220 g were used in this study. The animals were ovariectomized and randomly divided into four groups including, control and two groups which received 8 and 80 mg/kg Vitex agnus castus (VAC) ethanolic extract orally. The last groups were treated with 40 μg/kg of estradiol valerat. Step-through passive avoidance (STPA) test was used for the evaluation of learning and memory. The hippocampal estrogen receptor α (ERα) expression was measured using Real-Time PCR.
  
  
  RESULTS
  The results demonstrated that VAC extract or estradiol had better performance on step-through passive avoidance test than control group (all P<0.05). Moreover, administration of either estradiol or VAC extract increased the hippocampal mRNA level of ERα and prevented the decrease in uterine weight of ovariectomized rats.
  
  
  CONCLUSIONS
  Based on our data, VAC extract improves learning and memory in ovariectomized rats. The positive effect of VAC extract on learning and memory is possibly associated with an increase in ERα gene expression in the hippocampal formation.
authors.affiliation: Physiology- Pharmacology Research Center, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Allahtavakoli
authors.affiliation: Physiology- Pharmacology Research Center, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
authors.forename: Najmeh
authors.initials: N
authors.lastname: Honari
authors.affiliation: Department of Biology, School of Basic Sciences, Shahid Bahonar University of Kerman, Kerman, Iran.
authors.forename: Iran
authors.initials: I
authors.lastname: Pourabolli
authors.affiliation: Immunology of Infectious Diseases Research Center, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Kazemi Arababadi
authors.affiliation: Physiology- Pharmacology Research Center, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Ghafarian
authors.affiliation: Pharmaceutical Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Roohbakhsh
authors.affiliation: Department of Cardiology, School of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Esmaeili Nadimi
authors.affiliation: Physiology- Pharmacology Research Center, Rafsanjan University of Medical Sciences, Rafsanjan, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Shamsizadeh
keywords: Estrogen receptor alpha; Memory; Ovariectomy; Vitex agnus-castus