title: Antihypertensive effects of the essential oil of Alpinia zerumbet and its main constituent, terpinen-4-ol, in DOCA-salt hypertensive conscious rats.
abstract: The present study investigated the hypotensive responses to intravenous (i.v.) treatment with the essential oil of Alpinia zerumbet (EOAZ) and its main constituent, terpinen-4-ol (Trp-4-ol), in the experimental model of deoxycorticosterone-acetate (DOCA)-salt hypertensive rat. In both DOCA-salt hypertensive and uninephrectomized, normotensive rats, i.v. bolus injections of EOAZ (1-20 mg/kg) or Trp-4-ol (1-10 mg/kg) decreased mean aortic pressure (MAP) in a dose-related manner. However, hypotensive responses to Trp-4-ol were significantly greater than those evoked by the same doses of EOAZ (1-10 mg/kg). Treatment with DOCA-salt significantly enhanced the maximal percentage decreases in MAP evoked by EOAZ or Trp-4-ol. Likewise, both maximal percentage and absolute decreases in MAP elicited by i.v. injection of the ganglion blocker, hexamethonium (30 mg/kg), were significantly greater in DOCA-salt hypertensive than in control rats. In DOCA-salt hypertensive rats, neither hexamethonium (30 mg/kg, i.v.) nor methylatropine (1 mg/kg, i.v.) pretreatment affected the enhancement of EOAZ-induced hypotension. These results show that i.v. treatment with either EOAZ or Trp-4-ol dose-dependently decreases blood pressure in conscious DOCA-salt hypertensive rats, and this action is enhanced when compared with uninephrectomized controls. This enhancement could be related mainly to an increase in EOAZ-induced vascular smooth muscle relaxation rather than to enhanced sympathetic nervous system activity in this hypertensive model. The data further support our previous hypothesis that hypotensive effects of EOAZ are partially attributed to the actions of Trp-4-ol.
authors.affiliation: Departamento de Fisiologia e Farmacologia, Universidade Federal de Pernambuco, Recife-PE, Brasil. lahlou@npd.ufpe.br
authors.forename: Saad
authors.initials: S
authors.lastname: Lahlou
authors.forename: Leylliane Fátima Leal
authors.initials: LF
authors.lastname: Interaminense
authors.forename: José Henrique
authors.initials: JH
authors.lastname: Leal-Cardoso
authors.forename: Gloria Pinto
authors.initials: GP
authors.lastname: Duarte
mesh_terms: D032429:Alpinia; D000818:Animals; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D003900:Desoxycorticosterone / Q000031:analogs & derivatives*; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006973:Hypertension / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D007275:Injections, Intravenous; D008297:Male; D009822:Oils, Volatile / Q000627:therapeutic use*; D008517:Phytotherapy; D018515:Plant Leaves; D010938:Plant Oils / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D012965:Sodium Chloride; D013729:Terpenes / Q000627:therapeutic use*
chemical_list: D000959:Antihypertensive Agents; D009822:Oils, Volatile; D010938:Plant Oils; D013729:Terpenes; D003900:Desoxycorticosterone; D012965:Sodium Chloride; C034019:terpinenol-4