Preliminary Investigation Into The Acute Oral Toxicity Of Tephrosia vogelii Leaves In Mice

Abstract

An investigation was carried out on the acute toxicity of the crude methanolic leaf extract of Tephrosia vogelii Hook. f. (Fabaceae) in mice following oral administration of the extract at doses ranging from 10 to 10,000 mg per kg body weight. Propylene glycol was used as vehicle of administration. Clinical signs observed included initial excitation, restlessness, dyspnoea, foaming from the mouth, incoordination of gait and clonic convulsions. Gross post-mortem findings in the mice were enteritis, congestion of the lungs, liver, kidneys and spleen. Histopathologic findings included congestion, focal areas of necrosis and fatty degeneration in the liver; necrosis and oedema at the proximal and distal convoluted and collecting tubules of the kidneys; focal areas of necrosis in the epicardium and myocardium with mononuclear cellular infiltration. The median lethal dose (LD50) of the extract leaves was 134.16 mg/kg. The clinical signs observed in mice were similar to those reported for rotenone poisoning in mammals. It is concluded that the extract exerted toxic effects, which predominantly involved neurological disorders, hepatic, renal and cardiac necrotic changes in the mice.

Keywords: Tephrosia vogelii, Acute toxicity, LD50, Mice, Propylene glycol.

Nigerian Veterinary Journal Vol. 28 (2) 2007 pp. 47-52