بررسی اثر عصاره گیاه پنج انگشت (Vitex agnus castus) بر یادگیری و حافظه در موش های صحرایی اوارکتومی شده

Background and purpose: Menopause is associated with the cessation of ovarian activities and hypoestrogenemia causing many complications including learning and memory disorders. Recent studies have shown that these cognitive disabilities are due to the diminished neuroprotective and neurotrophic effects of estrogen and accordingly, estrogen therapy may prevent or overcome them. Since estrogen therapy has many side effects, using of other alternatives is of interest. The purpose of this study was to investigate the therapeutic effects of Vitex agnus castusa, a genus of tropical and sub-tropical flowering plants containing phytoestrogens, on learning and memory disorders in ovariectomized rats. Materials and methods: Forty two ovariectomized female Wistar rats (150 to 200g) were divided into five groups of seven as follows: control group, ovariectomy group, Vitex agnus castus extract at 8 mg/kg, Vitex agnus castus extract at 80 mg/kg, estradiol valerat at 40 μg/kg, and combination of tamoxifen (100 μg/kg) and Vitex agnus castus extract (80 mg/kg). The rats received these treatments orally for three months after ovariectomy. At the end of the therapeutic period, learning ability of the rats was measured using a shuttle box. Results: Compared to the ovariectomy group, estradiol valerat at 40 μg/kg, Vitex agnus castus extracts at 8 or 80 mg/kg and control group increased the level of the STLr factor and reverse results were observed for the TDC (Time spent in Dark Compartment) factor. However, the frequency of shock was diminished only in rats which Vitex agnus castus extracts at 80 mg/kg. Conclusion: Based on our data, Vitex agnus castus extract showed estrogen-like effects and improved memory disorder in ovariectomized female rats.