title: Vasodilator activity of the essential oil from aerial parts of Pectis brevipedunculata and its main constituent citral in rat aorta.
abstract: The essential oil of Pectis brevipedunculata (EOPB), a Brazilian ornamental aromatic grass, is characterized by its high content of citral (81.9%: neral 32.7% and geranial 49.2%), limonene (4.7%) and α-pinene (3.4%). Vasodilation induced by EOPB and isolated citral was investigated in pre-contracted vascular smooth muscle, using thoracic aorta from Wistar Kyoto (WKY) rats which was prepared for isometric tension recording. EOPB promoted intense relaxation of endothelium-intact and denuded aortic rings with the concentration to induce 50% of the maximal relaxation (IC50) of 0.044% ± 0.006% and 0.093% ± 0.015% (p < 0.05), respectively. The IC50 values for citral in endothelium-intact and denuded rings were 0.024% ± 0.004% and 0.021% ± 0.004%, respectively (p > 0.05). In endothelium-intact aorta, EOPB-induced vasorelaxation was significantly reduced by L-NAME, a nitric oxide synthase inhibitor. The vasodilator activity of citral was increased in the KCl-contracted aorta and citral attenuated the contracture elicited by Ca2+ in depolarized aorta. EOPB and citral elicited vasorelaxation on thoracic aorta by affecting the NO/cyclic GMP pathway and the calcium influx through voltage-dependent L-type Ca2+ channels, respectively.
authors.affiliation: Drug Development Program, Biomedical Science Institute, Federal University of Rio de Janeiro, Carlos Chagas Filho Avenue 373, 21941-902, Rio de Janeiro, RJ, Brazil.
authors.forename: Sharlene Lopes
authors.initials: SL
authors.lastname: Pereira
authors.forename: André Mesquita
authors.initials: AM
authors.lastname: Marques
authors.forename: Roberto Takashi
authors.initials: RT
authors.lastname: Sudo
authors.forename: Maria Auxiliadora Coelho
authors.initials: MA
authors.lastname: Kaplan
authors.forename: Gisele
authors.initials: G
authors.lastname: Zapata-Sudo
mesh_terms: D000080462:Acyclic Monoterpenes; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D029624:Ferns / Q000737:chemistry*; D066298:In Vitro Techniques; D008297:Male; D039821:Monoterpenes / Q000737:chemistry / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D035261:Plant Components, Aerial / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D051381:Rats; D014665:Vasodilator Agents / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000080462:Acyclic Monoterpenes; D039821:Monoterpenes; D009822:Oils, Volatile; D010936:Plant Extracts; D014665:Vasodilator Agents; C007076:citral