Effects of an aqueous extract of Bridelia ferruginea Benth (Euphorbiaceae) on mammalian heart activity

Bridelia ferruginea Benth (Euphorbiaceae) is used in African traditional medicine to treat many diseases. This plant has been used as diuretic. Since, the heart activity of this substance has not been investigated in scientifically controlled studies. The aim of the present study was to evaluate the effects of an aqueous extract of Bridelia ferruginea (SEA) on mammalian heart activity. The extracts were administrated intravenously at doses ranging from 0.58×10-3 g/kg to 38.82×10-3 g/kg b.w. to rabbits that had been anesthetized before. SEA significantly increased the PR interval, the P and T wave amplitude and the QRS complex while the ST interval decreased. In the presence of atropine (4×10-1 g/kg b.w.), SEA (45×10-3 g/kg b.w., significantly reduced the PR interval and caused an increase in the ST interval. At the same dose, SEA induced a decrease in the amplitude of the P wave and in the length of the ST interval after the propranolol (4×10-2 g/kg and 3×10-1 g/kg b.w.) use. The aqueous extract of this plant (10-8 to 10-2 mg/ml) induced a significant positive inotropic effect and various chronotropic effects on the isolated heart of rat. These results suggested that the extract of Bridelia ferruginea possess cholinomimetic and adrenomimetic substances.