Possible mechanisms of action of the neutral extract from Bidens pilosa L. leaves on the cardiovascular system of anaesthetized rats

• Published in: Phytotherapy research 2003-12, Vol.17 (10), p.1135-1139
• Main Authors: Dimo, T., Nguelefack, T. B., Tan, P. V., Yewah, M. P., Dongo, E., Rakotonirina, S. V., Kamanyi, A., Bopelet, M.
• Format: Article
• Language: English
• Subjects: Animals; Antihypertensive Agents - administration & dosage; Antihypertensive Agents - pharmacology; Antihypertensive Agents - therapeutic use; Bidens; Bidens pilosa; Biological and medical sciences; Blood Pressure - drug effects; Dose-Response Relationship, Drug; General pharmacology; Heart Rate - drug effects; Hypertension - chemically induced; Hypertension - prevention & control; hypotensive effect; Infusions, Intravenous; Medical sciences; Myocardial Contraction - drug effects; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Phytotherapy; Plant Extracts - administration & dosage; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; Plant Leaves; Rats; Rats, Wistar; Sodium Chloride; vasodilation
• ISSN: 0951-418X; 1099-1573
• DOI: 10.1002/ptr.1132

The aim of this study was to investigate the hypotensive and cardiac effects of the neutral extract from Bidens pilosa leaves. Intravenous administration of the extract resulted in a biphasic dose‐related hypotensive activity. In normotensive rats (NTR), B. pilosa decreased systolic blood pressure by 18.26%, 42.5% and 30% at doses of 10, 20 and 30 mg/kg, respectively. In spontaneously hypertensive rats (SHR), the decrease in systolic blood pressure was 25.77%, 38.96% and 28.64% at the above doses, respectively. These doses induced hypotension by 27%, 34.13% and 18.73% respectively in salt‐loaded hypertensive rats. In NTR, B. pilosa reduced heart rate by 23.68% and 61.18% at doses of 20 and 30 mg/kg, respectively. The force of contraction of the heart was only affected at 30 mg/kg. The initial phase of hypotensive response was partially inhibited by atropine while propranolol increased this effect. These results suggest that B. pilosa exhibited its first hypotensive effects by acting on the cardiac pump efficiency and secondly through vasodilation.