Abstract

The Cnidoscolous acontifolius hydroalcholic leaf extract (CAHLE) has been described as exhibiting biological activity in the central nervous system assays. The objectives of this study were to investigate the anxiolytic and antinociceptive effects of CAHLE in mice. Swiss albino mice (18 to 22 g) were randomly allotted to thirteen groups (n = 5 each). Groups 1 to 5 and 9 to 13 were treated with graded doses of CAHLE (100, 200, 400, 800 and 1600 mg/kg), Groups 6 and 7 received normal saline (10 ml/kg) and diazepam (1 mg/kg), respectively, while group 8 received 5 mg/kg of pentazocine hydrochloride (HCl). All drugs and test compounds were administered via intraperitoneal route except for pentazocine which was given subcutaneously. Data analysis was by one factor analysis of variance (ANOVA) followed by post hoc analysis using Student Newman Kuels multiple comparison tests. CAHLE treated mice showed increase open arm entries and open arm exploration time compared to control group in the elevated plus maze test. CAHLE treated mice also exhibited a time-dependent and a dose-dependent increase in tail flick latency. CAHLE treated mice also exhibited longer lasting protection from pain compared to standard. The study concluded that CAHLE possesses mild anxiolytic and analgesic properties to warrant its use in treatment of anxiety and relief of pain.

Key words: Anxiolytic, antinociceptive, central nervous system.