Hypotensive effect of the acetone fraction of the crude methanol extract of <i>Stereospermum kunthianum</i> (Bignoniaceae) stem bark

Abstract

Hypertension is a leading cause of cardiovascular disease worldwide. Despite a diversity of pharmacological agents to treat high blood pressure, suboptimal control remains a significant problem in as many as 43% of patients and this rate has not significantly improved over the two decades. There are several factors contributing to this including patient’s non-adherence due to complex drug regimes and medications side effects, under-treatment and treatment resistance. There, thus, remains a need to find herbal treatment to antihypertensive therapy that facilitate attainment of optimal blood pressure levels. Stereospermum kunthianum (Bignoniaceae) herb is used in Hausa ethnomedicine in treating bronchitis, venereal diseases, diarrhea, ulcers, leprosy, skin eruptions, respiratory ailments and gastritis. It is also used as abortifacient and as antihypertensive agent. General phytochemical investigation of methanolic extract of the stem bark of Stereospermum, kunthianum revealed the presence of sterol/triterpenes, coumarin, saponins, flavonoids, steroids, tannins, carbohydrates while alkaloids are rare. Acetone fraction of the crude methanol extract was subjected to biological studies to investigate the antihypertensive propertie s of the plant. The effect of acetone fraction of the Stereospermum kunthianum was compared with normal basal rhythm and Acetylcholine. The drugs and various doses of the extract were injected through a cannula inserted in the femoral vein. The extract dependently decreased Cat blood pressure and the decrease in the blood pressure was not blocked by atropine. The antihypertensive effects of the stem bark of Stereospermum kunthianum examined in this study showed that the plant is capable of exerting effect on the hypertensive patients .

Keywords: Antimicrobial; Stereospermum kunthianum; Phytochemical; Antihypertensive