title: Different mechanisms involved in the vasorelaxant effect of flavonoids isolated from Satureja obovata.
abstract: The inhibitory effects of naringenin, eriodictyol, and luteolin (10(-5) and 5 x 10(-5) M), previously isolated from Satureja obovata subsp. obovata var. valentina (Lamiaceae), on rat thoracic aorta were investigated. Flavonoids at the two concentrations assayed (10(-5) and 5 x 10(-5) M) showed different smooth muscle relaxant behaviour in the three phases involved in the noradrenaline (10(-6) M)-induced contractions. The three flavonoids showed an inhibitory effect of the phasic component in order of potency: luteolin > eriodictyol > naringenin. Luteolin and eriodictyol inhibited both tonic-I and tonic-II phases associated to the inhibition of PKC and calcium influx, respectively, whereas naringenin only inhibited the tonic-I phase associated to inhibition of PKC.
authors.affiliation: Departamento de Farmacología, Facultad de Farmacia, Universidad Complutense, E-28040 Madrid, Spain.
authors.forename: V R
authors.initials: VR
authors.lastname: Sánchez de Rojas
authors.forename: B
authors.initials: B
authors.lastname: Somoza
authors.forename: T
authors.initials: T
authors.lastname: Ortega
authors.forename: A M
authors.initials: AM
authors.lastname: Villar