Toxicity testing of senna occidentalis seed in rabbits

The effect was investigated of administering ground Senna occidentalis seed s to rabbits in different concentrations (1%, 2%, 3% and 4%) in the ration. The experiment lasted 30 days and the toxic effects of the plant were eval uated on the basis of weight gain, histopathological, biochemical and morph ometric parameters, as well as histochemistry and electron microscopy. Anim als that received the ration containing 4% ground S. occidentalis seeds gai ned less weight (p <0.05) and died in the third week. Histopathology reveal ed that the heart and liver were the main organs affected, with myocardial necrosis and centrolobular degeneration. There was a reduction in cytochrom e oxidase activity in the glycogenolytic fibres, together with muscle atrop hy, confirmed by the morphometric studies. Electron microscopy of the liver cells revealed dilated mitochondria, with destruction of the internal cris tae.