Extract Stem Bark of Hymenaea Rubriflora D: A New Perspective of Vasorelaxant Agent

In this study, was investigated the action of the hydroalcoholic extract of the stem bark of Hymenaea rubriflora Ducke (HR-HAc) on the vascular reactivity of rats in vitro and administered in vivo. Cumulative doses of HR-HAc promoted dose-dependent relaxation aortic rings of Wistar rats with functional endothelium, which was inhibited in the presence of L-NAME. After, animals (n=5) were treated with 25, 50 and 100 mg / kg or saline for four weeks for determination of reactivity to acetylcholine, nitroprusside and phenylephrine. Was observed increased acetylcholine relaxing potency at all doses, with a greater effect on G50 (pD2 = 7.8 ± 0.1, Emax = 95.6 ± 1.1) and a decreased contractile potency to phenylephrine in G25 (pD2 = 6.9 ± 0.06, Emax = 61.5 ± 6.0%) and G50 (pD2 = 6.6 ± 0.06, Emax = 71.0 ± 8.5%) when compared to GC in the presence and absence of endothelium (pD2 = 6.4 ± 0.1, 6.4 ± 0.1 and 6.9 ± 0.1, respectively). Cumulative doses of nitroprusside resulted in increased relaxing potency in all supplemented groups and maintained Emax at 100%. Concludes that HR-HAc has vasorelaxant capacity and endothelium-dependent contractile inhibitor, either applied directly to aortic rings or after treatment with in vivo supplementation, which places this extract as a potential antihypertensive agent for future studies.