title: Evaluation of n-hexane extract of Viola betonicifolia for its neuropharmacological properties.
abstract: Viola betonicifolia (whole plant) has been used as a sedative and in various nervous disorders in Pakistani traditional medicines. The n-hexane extract of the whole plant of V. betonicifolia (HEVB) was investigated for neuropharmacological properties such as anxiolytic, muscle relaxant, sleep induction, antidepressant and sedative to ascertain its folk use. Anxiolytic activity was tested using the staircase test, while the muscle relaxing property of the extract was tested in various muscle relaxant paradigms, i.e. chimney test, traction test, rota rod and inclined plane. In anxiolytic and muscle relaxant tests, HEVB (0.3, 0.4 and 0.5 g/kg, i.p.), diazepam (1 mg/kg, i.p.) or distilled water (10 ml/kg i.p.) were administered 30, 60 and 90 min before performing the tests in mice. HEVB was also screened for a sleep-inducing effect. The antidepressant activity was determined by using the forced swimming test (FST), while line crossing in a special box was used for locomotor activity. HEVB showed a significant (P < 0.05) dose-dependent anxiolytic action in the staircase test. In muscle relaxant paradigms, a dose-dependent muscle relaxation was observed. For the phenobarbitone sleep induction test, HEVB notably (P < 0.05) reduced the latency time and increased the total sleeping duration. However, HEVB was devoid of any antidepressant activity, while the movements of mice were reduced significantly (P < 0.05) in locomotor activity. The results suggest that HEVB has anxiolytic, muscle relaxant, sleep-inducing (sedative) activity and, thus, provides pharmacological justification for the use of this plant as a sedative and for the relief of various nervous disorders.
authors.affiliation: Department of Pharmacy, University of Peshawar, Peshawar, Pakistan. drnaveedrph@gmail.com
authors.forename: Naveed
authors.initials: N
authors.lastname: Muhammad
authors.forename: Muhammad
authors.initials: M
authors.lastname: Saeed
authors.forename: Haroon
authors.initials: H
authors.lastname: Khan
authors.forename: Ikramul
authors.initials: I
authors.lastname: Haq
mesh_terms: D000818:Animals; D014151:Anti-Anxiety Agents / Q000737:chemistry / Q000494:pharmacology*; D000928:Antidepressive Agents / Q000737:chemistry / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects*; D005260:Female; D006586:Hexanes / Q000737:chemistry*; D006993:Hypnotics and Sedatives / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009480:Neuropharmacology / Q000379:methods; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology*; D032413:Viola / Q000737:chemistry*
chemical_list: D014151:Anti-Anxiety Agents; D000928:Antidepressive Agents; D006586:Hexanes; D006993:Hypnotics and Sedatives; D010936:Plant Extracts; C026385:n-hexane