Effect of Tulbaghia violacea on the blood pressure and heart rate in male spontaneously hypertensive Wistar rats

Tulbaghia violacea Harv. (Alliaceae) is a small bulbous herb which belongs to the family Alliaceae, most commonly associated with onions and garlic. In South Africa, this herb has been traditionally used in the treatment of various ailments, including fever, colds, asthma, paralysis, hypertension and stomach problems. The aim of this study was to evaluate the effect of methanol leaf extracts (MLE) of Tulbaghia violacea on the blood pressure (BP) and heart rate (HR) in anaesthetized male spontaneously hypertensive rats; and to find out the mechanism(s) by which it acts. The MLE of Tulbaghia violacea (5–150mg/kg), angiotensin I human acetate salt hydrate (ang I, 3.1–100μg/kg), angiotensin II human (ang II, 3.1–50μg/kg), phenylephrine hydrochloride (phenylephrine, 0.01–0.16mg/kg) and dobutamine hydrochloride (dobutamine, 0.2–10.0μg/kg) were infused intravenously, while the BP and HR were measured via a pressure transducer connecting the femoral artery and the Powerlab. Tulbaghia violacea significantly (p