['Gentiana floribunda was investigated for the possible hypotensive and vasodilator activities in an attempt to rationalize its traditional use in hypertension.', 'The crude extract of Gentiana floribunda (Gf.Cr) was studied in anaesthetized rats and isolated thoracic aorta tissues.', 'Gf.Cr which tested positive for presence of flavonoids, saponins, sterols, tannins and terpenes caused dose-dependent (3.0-100\u2009mg/kg) fall in arterial blood pressure (BP) of rats under anaesthesia. In rat aortic ring preparations denuded of endothelium, Gf.Cr at concentration range of 1.0-10\u2009mg/mL relaxed high K+ (80\u2009mM) and phenylephrine (PE, 1\u2009μM)-induced contractions and shifted Ca++ dose-response curves to right, similar to that caused by verapamil. It also suppressed PE (1\u2009μM) control peak responses at 0.3-1.0\u2009mg/mL, obtained in Ca++-free medium, as exhibited by verapamil. Pre-treatment of tissues with Gf.Cr produced rightward non-parallel shift of PE-curves with decline of maximum contractile response. The vasodilator effect of Gf.Cr was endothelial-independent, as it was not blocked by Nω-nitro-L-arginine methyl ester hydrochloride, atropine and indomethacin in endothelium-intact aortic tissues.'] Is hypotensive effect of Gentiana floribunda mediated through Ca++ antagonism pathway?