Abstract

The leaves of Gongronema latifolium is used in Nigeria for the treatment of diarrhoea and thus, the phytochemical constituents as well as the acute toxicity of the ethanol extract of the leaves of G. latifolium and its effects [at graded doses of 200, 400 and 600 mg/kg body weight (b.w)] against castor oil-induced diarrhoea models in rats were evaluated. The parameters used for the evaluation of the castor oil-induced diarrhoea were: reductions in the wetness of faeces and rate of defaecation. To further understand the probable mechanisms of its anti-diarrhoeal action, its effects were evaluated on gastro-intestinal motility and castor oil-induced enteropooling. The phytochemical screening of the ethanol extract of the leaves of G. latifolium revealed the presence of saponins, tannins, alkaloids, flavonoids, glycosides and cardiac glycosides. The ethanol extract of the leaves of G. latifolium at the tested doses caused significant (p<0.05) dose-dependent reductions of castor oil-induced diarrhoea, gastro-intestinal motility and castor oil-induced enteropooling in the treated rats. The results were comparable with those of the standard anti-diarrhoeal drug, atropine sulphate (2.5 mg/kg b.w). The extract was found to be non-toxic even at a dose as high as 5000 mg/kg b.w. The results indicate that the ethanol extract of the leaves of G. latifolium contains compounds with anti-diarrhoeal effect and may possibly originate an anti-diarrhoeal drug in time to come.

Key words: Gongronema latifolium, diarrhoea, castor oil and atropine sulphate.