RESUMEN
The aim of the present study is to determine the chemical composition of the essential oil extracted from the flowers of Anthemis mauritiana Maire & Sennen (EOAM) and to investigate its antispasmodic effects on intestinal smooth muscle. The phytochemical composition was revealed by gas chromatography-mass spectrometer. Eighteen compounds were identified representing 90.56% of the oil. The major constituents were described as alpha-pinene (27.02%), sabinene (15.25%), cedrenol (14.53%) germacrene (9.61%) geraniol formate (6.82%), and caryophylene (5.38%). EOAM (10-100 microg/ml) elicited reversible relaxation of spontaneous contractions of isolated rabbit jejunal smooth muscle preparations, and similarly inhibited contractions induced by high-potassium solution ([K(+)](o) = 76 mM) and carbachol (10(-6) M) with IC(50) values of 14.98 and 27.29 microg/ml, respectively. Furthermore, EOAM exhibited an inhibitory effect on the dose-response curves induced by carbachol and CaCl(2) on rat jejunum preparations. These results clearly demonstrated the antispasmodic effect of EOAM which was strongly suggested to be mainly due to an inhibitory effect on Ca(2+) influx through the membrane of jejunal smooth muscle cells.