Abstract
Background: Ceiba pentandra (L.) Gaertner (Malvaceae) a plant widely spread in the world, particularly in sub-Saharan Africa where it is used to handle several pathologies like high blood pressure without scientific evidence by experimental scientific works.

Aim and Objective: The purpose of this study is to show how a hydroethanolic leaves extract of Ceiba pentandra (FCP) produces relaxant effects in porcine coronary, rat mesenteric artery, carotid, femoral arteries, and thoracic aorta and to determine the mechanisms which lie beneath this effect.

Materials and Methods: Porcine coronary, rat mesenteric, carotid, and femoral arteries and thoracic aorta rings were suspended in organ chambers for recording of changes in isometric forces. Rings with endothelium were incubated or not with L-nitroarginine to block nitric oxide (NO) synthase, manganese (III) tetrakis(1-methyl-4-pyridyl)porphyrin, polyethylene glycol catalase (CAT), an inhibitors of intracellular production reactive oxygen species (ROS); CAT, an inhibitor of extracellular ROS; wortmannin, an inhibitor of redoxsensitive pathway phosphoinositide 3-kinase (PI3 kinase)/Akt; (4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo [3,4-d] pyrimidine), an inhibitor of Src kinase; apamin, an inhibitor of small conductance potassium channels calcium dependent (SKCa) and tram-34, an inhibitor of intermediary conductance potassium channels calcium dependent (IKCa); and indomethacin, an inhibitor of cyclooxygenase before contraction with U46619 or phenylephrine and a concentration-relaxation curve to FCP.

Results: Some experiments show that endothelium was taken away before contraction with U46619 and concentration relaxation to FCP. The hydroethanolic leaves extract of C. pentandra produces a vasodilatory result in porcine coronary artery pre-contracted with U46619. This effect is endothelium dependent and is mediated by NO. FCP generates, as well, vasorelaxant results in superior mesenteric arteries, carotid arteries, thoracic aorta, and femoral arteries from rat. C. pentandra generates vascular relaxation which can be the explanation of the benefic effect of this plant in the treatment of high blood pressure (HBP) in Africa.

Conclusion: C. pentandra holds vasorelaxants properties on pig coronary artery, thoracic aorta, the main superior mesenteric artery, and femoral and carotid artery from rat justifying its utilization in the treatment of the arterial HBP. This effect necessitates the presence of a functional endothelium and passes by the redox-sensitive pathway Src kinase and PI3-kinase/Akt.

Key words: Ceiba pentandra; Vasorelaxant Effects; Porcine Coronary; Rat Arteries