The most significant effect, observed in the preliminary pharmacological evaluation of the whole ethanol extract and the alkaloidal fraction of Cephäelis axillaris, was the hyperemia of ears and external mucosas which was most probably due to an alpha-adrenergic blocking activity. In addition, both samples also induced a marked hypotension in normotensive as well as hypertensive (SHR) rats and inhibited the increases of blood pressure induced by i.v. administration of noradrenaline in pithed rats. The structures of the major alkaloidal components of the extract were elucidated on the basis of chemical characterization assays and IR, UV, 1H and 13C one and two-dimensional NMR analyses.
(EN)
