Alchornea cordifolia (Euphorbiaceae) is a very prized plant among traditional healers in Africa. Its leaves are used for its antipyretic properties in traditional areas. The aim of our study is to determine the acute toxicity and the antipyretic activity of a methanolic extract of Alchornea cordifolia leaves. Acute toxicity was assessed by measuring mortality, changes in body weight, spontaneous movements, and normal rectal temperature in mice. Antipyretic activity was evaluated by brewer's yeast-induced hyperpyrexia in rats according to Teotino method (1963). The antipyretic effect of methanolicextract of Alchornea cordifolia leaves was compared with paracetamol (100 mg/kg bw) orally. Groups of mice treated with doses of 6500; 3250; 1625 and 812.5mg/kg of the extract did not show any mortality, nor significant alteration of body weight, nor alteration of spontaneous movements. However, incomplete reversed dose-dependent hypothermic activity was observed with doses of 50.78; 101.56; 203.12; 406.25; and 812.5 mg/kg p.o. of the extract, showing acute toxicity of this plant. In the antipyretic assay, the extract with doses of 50.78; 101.56; 203.12; 406.25; and 812.5 mg/kg p.o. exhibited a significant dose-dependent antipyretic activity similar to paracetamol (100 mg/kg bw) in rats. Thus Alchornea cordifolia may inhibit prostaglandins-biosynthesis from hypothalamus. Our results support claims on its traditional uses in management of fever. However Alchornea cordifolia may affect hypothalamus not only during fever but also when body temperature is normal.

Anacardium occidentale Linn. (Anacardiaceae) is a plant largely used in Africa for the treatment of different diseases. In Côte d'Ivoire it's commonly used for the treatment of hypertension. The present study was carried out in order to assess the effects of Anacardium occidentale extract (ANOE) on cardiovascular parameters in animal models. A mercury manometer kymograph of Ludwig was used to measure the blood pressure of normotensive rabbits in control conditions (normal physiological solution) and under the influence of ANOE. The contractile activity of an isolated rat heart was also measured in control conditions and under the influence of ANOE in different physiological media using a modified Langendhorff (1895) apparatus. The aqueous Anacardium occidentale (ANOE) bark extract applied intravenously in different doses (12, 40, 90, and 167 mg/kg b.w.), produced a significant dose-dependent decrease in blood pressure of previously normotensive rabbits (up to 89% vs control). Atropine (1 mg/ml) pre-treatment failed to reverse the hypotensive effects elicited by the extract. ANOE applied to isolated rat heart preparations in different concentrations (0.01, 0.1, 1.0, and 10 µg/ml) induced negative inotropic and chronotropic effects. Atropine pre-treatment of heart preparations (0.1 μg/ml) failed to reverse the negative effects induced by ANOE. The extract's action on heart contractile activity studied in modified culture media further confirmed its cardio-inhibitory effects. ANOE induced strong hypotensive and cardio-inhibitory effects in animal models.

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