Calcium-channel blockade-mediated blood pressure-lowering and vasorelaxant effects of Brassica oleracea

Background: Brassica oleracea L. (Brassicaceae), commonly known as cabbage, is usually used for dietary purposes and is also known for many medicinal uses, including blood pressure. Objectives: The current research study aimed to authenticate the traditional claims of B. oleracea L. for hypertension on a scientific basis using in vivo and in vitro pharmacological techniques. Methods: Crude extract of B. oleracea L. was evaluated for its hypotensive and vasorelaxant effects in normotensive anesthetized wistar rats using an invasive blood pressure-measuring technique and isolated rat thoracic aorta, respectively. Results: Normotensive anaesthetized rats used in experiments showed a gradual decrease in blood pressure parameters and heart rate when treated with Bo.Cr (0.1–100 mg/kg) comparable to verapamil (0.01–30 mg/kg). Whereas, in isolated aortic tissue, Bo.Cr (0.01-3 mg/ml) exhibited complete relaxation on high K+ [80 mM] and phenylephrine (1 µM)-mediated contractions. Crude extract at doses of 0.3 and 1 mg/ml also showed a reduction in response to Ca2+ concentration-response curves. Conclusion: Results indicate calcium channel-blocking activity, a possible cause of the blood pressure-lowering and vasodilator effects of B. oleracea.