ANXIOLYTIC AND MOTOR COORDINATION ACTIVITY OF ETHANOLIC AND AQUEOUS EXTRACTS OF DENDROPHTHOE FALCATA LEAVES IN MICE

The aim of the present study was to evaluate the anxiolytic effects and motor activity of ethanolic and aqueous extracts of leaves of Dendrophthoe falcata (DF) in mice. Swiss albino mice were treated orally with ethanolic and aqueous extracts of DF leaves (250 mg/kg and 500 mg/kg) and distilled water along with alprazolam (1 mg/kg) intraperitoneally for seven days and then exposed to Elevated Plus Maze (EPM) and Light Dark Box (LDB). The effects of the plant extracts on motor coordination were evaluated by Rota rod test. We further investigated the mechanism of action underlying the anxiolytic-like effect of the extracts by pre-treating animals with antagonist of benzodiazepine (flumazenil, 3mg/kg) prior to evaluation using EPM and LDB. Mice treated with ethanol DF extract (250 mg/kg) showed significant increase in; percentage of open arm entries, time spent in open arms of EPM and decrease in motor coordination in Rotarod test. Furthermore, the ethanol DF extracts (250 mg/kg and 500 mg/kg) significantly increased the percentage of time spent and number of transitions in the Light box in LDB test, comparable to that of the alprazolam, indicating the anxiolytic effects of the substance. The result shows that the DF extracts might dose-dependently increase chloride ion influx, which was blocked by co-administration of negative allosteric modulator, flumazenil, suggesting a GABA(A) receptor mediated mechanism of action. Taken altogether, the present study demonstrates that the ethanolic leaves extract of DF has anxiolytic activity. The extract might act at the benzodiazepine recognition site of the GABA-benzodiazepine receptor complex. INTRODUCTION: Anxiety disorders are the most common and prevalent behavioral disorders that can result in significant impairment of function and quality of life 1 . Currently, the benzodiazepines and the SSRIs are the most commonly employed medicinal treatments for the common clinical anxiety disorders. Benzodiazepines are potent anxiolytics but can be associated with problematic sedation, memory problems, tolerance and discontinuation symptoms. QUICK RESPONSE CODE DOI: 10.13040/IJPSR.0975-8232.6(4). 1753-60 Article can be accessed online on: www.ijpsr. com DOI link: http://dx.doi. org/10.13040/IJPSR.0975-8232.6(4). 1753-60 Novel compounds however seek to target synaptic and extrasynaptic GABA receptor subtypes in order to selectively control neuronal excitability in networks involved in anxiolysis 2 . Research in the area of herbal psychopharmacology has revealed a variety of promising medicines that may provide benefit in the treatment of general anxiety and specific anxiety disorders 3 . Dendrophthoe falcata (L.f) Ettingsh is one of the hemiparasitic plants that belong to the Loranthaceae family of mistletoes. The whole plant is used in indigenous system of medicine as cooling, bitter, astringent, aphrodisiac, narcotic and diuretic and is useful in treating pulmonary tuberculosis, asthma, menstrual disorders, swelling wounds, ulcers, renal and vesical calculi and vitiated conditions of kapha and pitta 4, 5 . Dendrophthoe falcata is reported to contain biological active substances such as