Chemical composition and cardiovascular effects induced by the essential oil of Cymbopogon citratus DC. Stapf, Poaceae, in rats

Abstract

Cymbopogon citratus DC. Stapf, Poaceae, is used in the folk medicine for hypertension treatment. This work investigated the chemical composition and cardiovascular effects in rats of C. citratus essential oil (EOCC). A phytochemical screening demonstrated the presence of eight constituents, being geranial the major compound (43.08%). In rats, EOCC (1, 5, 10, and 20 mg/kg, i.v.) induced transient hypotension and bradycardia that were attenuated by atropine and sodium thiopental, but not by L-NAME or indomethacin. In rings of rat superior mesenteric artery pre-contracted with phenylephrine, EOCC (1 to 3000 µg/mL) induced relaxation that was not affected after removal of the endothelium, after TEA or in rings pre-contracted with KCl (80 mM). Furthermore, EOCC (1000 µg/mL) was not able to induce additional effect on maximal relaxation of nifedipine (10 µM). In conclusions, EOCC induces hypotension, possibly by reduction in vascular resistance caused by inhibition of the Ca2+ influx, and bradycardia probably due to an activation of cardiac muscarinic receptors.