Abstract

Most of the sedative drugs cause dose-dependent depression of the central nervous system (CNS) leading to hypnosis and possibly anaesthesia, however, these agents are associated with some side effects ranging from digestive, respiratory, immune system dysfunctions, cognitive function deterioration, tolerance, and physical dependence, hence investigations of newer and safer agents is therefore imperative. The current study sought to investigate the sedative-hypnotic effects of methanolic stem bark extract of Ficus abutilifolia in mice. Phytochemical constituents and sedative-hypnotic activity of the extract were investigated. Twenty Swiss albino mice were used for the experiment, the animals were randomly divided into four groups of five mice each. The mice in groups 1 and 2 were injected with the extract at the dose of 100 and 200 mg/kg, respectively, those in group 3 were injected with xylazine at the dose rate of 10 mg/kg, while the control group 4 mice received nothing at the beginning of the experiment. All the four experimental groups were injected with ketamine at the dose rate of 100 mg/kg after 30 min, all the treatments during the experimental trial were administered intraperitoneally (IP). Phytochemical analysis of the stem bark extract revealed the presence of carbohydrates, reducing sugars, cardiac glycosides, cardinolides, steroids and triterpenes, saponins, tannins, condensed tannins and flavonoids, while, anthraquinones, anthracene derivates and alkaloids were absent. The results show no significant difference (P ≥ 0.05) on the sleep onset time between the four groups, however, statistically significant difference (P<0.05) was recorded in the sleep duration time between the groups The group pre-treated with low dose of the extract (100 mg/kg) before ketamine administration after 30 min exhibited longer sleeping duration time. The mice were sedated for some time after arousal from sleep. Conclusively, our finding suggests that methanolic stem bark extract of F. abutilifolia possess sedative-hypnotic potentials that may require further scientific elucidations.

Key words: F. abutilifolia, mice, stem bark extract, sedative-hypnotic activity.