title: Vasorelaxant effects of 1-nitro-2-phenylethane, the main constituent of the essential oil of Aniba canelilla, in superior mesenteric arteries from spontaneously hypertensive rats.
abstract: The present study investigated the mechanisms underlying the vasorelaxant effects of the essential oil of Aniba canelilla (EOAC) and its main constituent 1-nitro-2-phenylethane (NP) in isolated superior mesenteric artery from spontaneously hypertensive rats (SHRs). At 0.1-1000 μg/mL, EOAC and NP relaxed SMA preparations pre-contracted with 75 mMKCl with IC(50) (geometric mean [95% confidence interval]) values of 294.19 [158.20-94.64] and 501.27 [378.60-624.00] μg/mL, respectively); or with phenylephrine (PHE) (IC(50)s=11.07 [6.40-15.68] and 7.91 [4.08-11.74) μg/mL, respectively). All these effects were reversible and remained unaltered by vascular endothelium removal. In preparations maintained under Ca(2+)-free conditions, EOAC and NP (both at 600 μg/mL) reduced the PHE-, but not the caffeine-induced contraction. In Ca(2+)-free and high K(+) (75 mM) medium, the contractions produced by CaCl(2) or BaCl(2) were reduced or even abolished by EOAC and NP at 100 and 600 μg/mL, respectively. EOAC and NP (both at 10-1000 μg/mL) also relaxed the contraction evoked by phorbol dibutyrate (IC(50)=52.66 [10.82-94.64] and 39.13 [31.55-46.72] μg/mL, respectively). It is concluded that NP has a myogenic endothelium-independent vasorelaxant effects and appears to be the active principle of the EOAC. Vasorelaxant effect induced by both EOAC and NP is preferential to receptor-activated pathways and it appears to occur intracellularly more than a superficial action restricted to the membrane environment such as a simple blocking activity on a given receptor or ion channel.
authors: Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, PE, Brazil.
authors: Leylliane de Fátima Leal
authors: Lde F
authors: Interaminense
authors: Fernanda Elizabethe
authors: FE
authors: dos Ramos-Alves
authors: Rodrigo José Bezerra
authors: RJ
authors: de Siqueira
authors: Fabiano Elias
authors: FE
authors: Xavier
authors: Gloria Pinto
authors: GP
authors: Duarte
authors: Pedro Jorge Caldas
authors: PJ
authors: Magalhães
authors: José Guilherme Soares
authors: JG
authors: Maia
authors: Pergentino José da Cunha
authors: PJ
authors: Sousa
authors: Saad
authors: S
authors: Lahlou
mesh_terms: D000818:Animals; D001555:Benzene Derivatives / Q000494:pharmacology*; D002110:Caffeine / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D019770:Lauraceae; D008297:Male; D017538:Mesenteric Artery, Superior / Q000187:drug effects* / Q000502:physiology; D009822:Oils, Volatile / Q000494:pharmacology*; D010656:Phenylephrine / Q000494:pharmacology; D024301:Plant Bark; D051381:Rats; D011918:Rats, Inbred SHR; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: C541822:1-nitro-2-phenylethane; D001555:Benzene Derivatives; D009822:Oils, Volatile; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D010656:Phenylephrine; D002110:Caffeine; D002118:Calcium