Hydrocotyle bonariensis Comm ex Lamm (Araliaceae) leaves effects on rabbits blood pressure and electrocardiogram

Hydrocotyle bonariensis Comm ex Lamm (Araliaceae) is traditionally used to treat various pathologies like hypertension. This work aims to evaluate the impact of hydro-ethanolic extract of its leaves on the blood pressure and cardiac activity of rabbits, and then to compare its hypotensive effect to conventional hypotensives. Intravenous injection of the hydro-ethanolic leaf extract (10; 20; 40; 80 and 160 mg /kg body weight) of H. bonariensis induced a significant decrease in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP) in rabbits. Injection of same doses induced at 80 and 160 mg /kg on the rabbit’s ECG a decrease in P wave amplitude and heart rate but caused a rise in RR interval. Comparison of the hypotensive effect of 40 mg/kg extract with the effects of 1.5 mg/kg propranolol, 0.1 mg/kg nicardipine and 1.5 mg/kg furosemide in rabbits shows that there is insignificant variation between the hypotensive effect of the extract and the hypotensive effects of these products at the doses administered in rabbits. These results confirm the hypotensive effect of H. bonariensis leaf extract, thus justifying its utilization managing high blood pressure traditionally. Key words: Hydrocotyle bonariensis, hypertension, electrocardiograms (ECGs), hypotensives.