Evaluation of Analgesic and Anti-Inflammatory Activities of the Methanolic Leaf Extract of Adenodolichos Paniculatus (Hua)

Abstract

The plant Adenodolichos paniculatus is a shrub of up to 4m high of Savanna (bush and jungle) from Guinea to Northern Nigeria and across to Sudan. The plant has been reported to be used traditionally in tooth ache, blennorrhea and in treatment of burns. In this work, the analgesic and anti-inflammatory activities of the methanolic leaf extract of Adenodolichos paniculatus (MAP) were studied. MAP (75, 150 and 300 mg/kg i.p) was evaluated for analgesic and anti-inflammatory activities using acetic acid induced writhing and Carrageenan induced paw edema in mice and rats respectively. The methanolic leaf extract exhibited significant (P < 0.05) and dose dependent analgesic and anti-inflammatory effects comparable to that of the reference drug Ketoprofen (20 mg/kg body weight i.p) which is a standard analgesic and anti-inflammatory drug. The preliminary phytochemical screening of the MAP revealed the presence of flavonoids, tannins, glycosides, anthraquinones and phenols. The intraperitoneal median lethal dose (LD 50 ) of MAP in mice was found to be 1113.3mg/kg and the oral LD 50 in rats was found to be greater than 5,000 mg/kg. body weight. The findings suggest that the MAP possesses analgesic and anti-inflammatory activities, and supports the ethno medical claims of the use of the plant in the management of painful and inflammatory conditions.