Enhanced hypotensive effects of the essential oil of Ocimum gratissimum leaves and its main constituent, eugenol, in DOCA-salt hypertensive conscious rats.
The cardiovascular effects of intravenous (i.v.) treatment with the essential oil of Ocimum gratissimum (EOOG) and its main constituent, eugenol (Eug) were investigated in the experimental model of deoxycorticosterone acetate (DOCA-salt)-hypertensive rats. In both conscious DOCA-salt hypertensive rats and their uninephrectomized controls, i.v. bolus injections of EOOG (1 - 20 mg/kg) or Eug (1 - 10 mg/kg) induced dose-dependent hypotension and bradycardia. Treatment with DOCA-salt significantly enhanced the maximal decreases in mean aortic pressure (MAP) elicited by hexamethonium (30 mg/kg, i.v.) as well as the hypotensive responses to both EOOG and Eug without affecting the bradycardia. However, the enhancement of EOOG-induced hypotension in hypertensive rats remained unaffected by i.v. pretreatment with either hexamethonium (30 mg/kg) or methylatropine (1 mg/kg). These results show that i.v. treatment with EOOG or Eug dose-dependently decreased blood pressure in conscious DOCA-salt hypertensive rats, and this action is enhanced when compared with uninephrectomized controls. This enhancement appears related mainly to an increase in EOOG-induced vascular smooth relaxation rather than to enhanced sympathetic nervous system activity in this hypertensive model.
Interaminense
Leylliane Fátima Leal
LF
Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, Pernambuco-PE, Brazil.
Leal-Cardoso
José Henrique
JH
Magalhães
Pedro Jorge Caldas
PJ
Duarte
Gloria Pinto
GP
Lahlou
Saad
S
D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D003900:Desoxycorticosterone; D004305:Dose-Response Relationship, Drug; D005054:Eugenol / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D006973:Hypertension / Q000139:chemically induced / Q000517:prevention & control*; D007262:Infusions, Intravenous; D008297:Male; D031339:Ocimum; D008517:Phytotherapy; D010938:Plant Oils / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D012965:Sodium Chloride
D000959:Antihypertensive Agents; D010938:Plant Oils; D005054:Eugenol; D003900:Desoxycorticosterone; D012965:Sodium Chloride