title: Vasorelaxant effects of 1-nitro-2-phenylethene in rat isolated aortic rings.
abstract: Previously, we showed that nitro-2-phenylethane is a vasorelaxant constituent of the essential oil of Aniba canelilla. Here, we investigated the mechanisms underlying the vascular effects of 1-nitro-2-phenylethene (NPe), a structural analog of 1-nitro-2-phenylethane obtained synthetically, in rat isolated thoracic aortic preparations. At 0.1-100 μg/mL, NPe similarly relaxed endothelium-intact or endothelium-denuded aortic preparations pre-contracted with 60mM KCl or with phenylephrine (PHE, 1 μM). Vasorelaxant effects of NPe against PHE-induced contractions remained unaffected following blockade of potassium channels by TEA, and inhibition of either nitric oxide synthase by l-NAME, cyclooxygenase by indomethacin or guanylate cyclase by ODQ. In preparations maintained under Ca(2+)-free conditions, NPe significantly reduced the contractions induced (i) by PHE, but not those evoked by caffeine, (ii) by CaCl2 in either PHE (in the presence of 1 μM verapamil)- or KCl-stimulated preparations, (iii) by extracellular Ca(2+) restoration in thapsigargin-treated aortic preparations, and (iv) by the activator of protein kinase C phorbol-12,13-dibutyrate or the inhibitor of protein tyrosine phosphatase sodium orthovanadate. It is concluded that NPe induced an endothelium-independent vasorelaxation with potency greater than its structural analog 1-nitro-2-phenylethane. Such action appears to occur intracellularly probably through inhibition of contractile events that are clearly independent of Ca(2+) influx from the extracellular milieu.
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Ceará, CE, Brazil. Electronic address: loeste.arruda@gmail.com.
authors.forename: Loeste
authors.initials: L
authors.lastname: Arruda-Barbosa
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Ceará, CE, Brazil. Electronic address: karilane.fisio@gmail.com.
authors.forename: Karilane Maria Silvino
authors.initials: KM
authors.lastname: Rodrigues
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Ceará, CE, Brazil. Electronic address: vasconcelos.18@gmail.com.
authors.forename: Francisco das Chagas Vasconcelos
authors.initials: Fd
authors.lastname: Souza-Neto
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, PE, Brazil. Electronic address: duarte.gloria@gmail.com.
authors.forename: Gloria Pinto
authors.initials: GP
authors.lastname: Duarte
authors.affiliation: Department of Pharmacy, Federal University of Pará, Belém, PA, Brazil. Electronic address: lqfmed@gmail.com.
authors.forename: Rosivaldo S
authors.initials: RS
authors.lastname: Borges
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Ceará, CE, Brazil. Electronic address: pjcmagal@ufc.br.
authors.forename: Pedro Jorge Caldas
authors.initials: PJ
authors.lastname: Magalhães
authors.affiliation: Department of Physiology and Pharmacology, Federal University of Ceará, CE, Brazil. Electronic address: lahlou562@gmail.com.
authors.forename: Saad
authors.initials: S
authors.lastname: Lahlou
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects* / Q000378:metabolism; D001555:Benzene Derivatives / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D006162:Guanylate Cyclase / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism; D019331:NG-Nitroarginine Methyl Ester / Q000378:metabolism; D010656:Phenylephrine / Q000494:pharmacology; D015221:Potassium Channels / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: C541822:1-nitro-2-phenylethane; D001555:Benzene Derivatives; D015221:Potassium Channels; D014665:Vasodilator Agents; D010656:Phenylephrine; D011493:Protein Kinase C; D006162:Guanylate Cyclase; D002118:Calcium; D019331:NG-Nitroarginine Methyl Ester
keywords: 1-Nitro-2-phenylethene; 1-Nitro-2-phenylethene (PubChem CID: 5284459); Endothelium-independent vasorelaxation; Isolated thoracic aorta; Myogenic; Normotensive rat