Pharmacological Justification for the Ethnomedicinal Use of Amblygonocarpus Andongensis Stem Bark in Pain Relief

Amblygonocarpus andongensis (family:Mimosaceae) is ethnomedicinally used in Northern Nigeria for the relief of pain. The methanolic extract of the plant stem bark was evaluated for anti-nociceptive activity using acetic acid-induced writhing model and formalin test in mice. Anti-inflammatory property was tested on egg albumin-induced oedema in rats while agar dilution method was used for antimicrobial effect. The acute toxicity effect (LD50) was also determined via intraperitoneal route. The results showed the LD50 value to be 547.7 mg/kg i.p. There was a significant (P < 0.05) dose-dependent reduction of acetic acid-induced pain at 50, 100, 200 mg/kg i.p. The extract at the same doses significantly ( P < 0.05) inhibited pains in both early and late phases of the formalin test. However, the extract showed neither anti-inflammatory nor anti-microbial effects. The results corroborate the folkloric use of the plant.