EFFECTS OF PANAXADIOL SAPONINS ISOLATED FROM PANAXNOTOGINSENG ON INTRACELLULAR AND EXTRACELLULAR CALCIUM

Panaxadiol saponins (PDS ) contain saponins Panax notoginseng B1 and E. The spontaneous beating induced by isoproterenol in isolated rat right atria and the increase of contractile force induced by Ca2+ in isolated guinea pig colon were inhibited by PDS 75 and 150 mug . ml-1, respectively and perhexiline 6.25 and 12.5 mumol . L-1, respectively. It suggested that PDS could block the potential-dependent and receptor-operated calcium channel in smooth muscle. PDS 150 mug . ml-1 and perhexiline 6.25 mumol . L-1 depressed the contractile force induced by norepinephrine and Ca2+ in isolated rat aortic strips in Ca2+-free Krebs' solution. It suggested that PDS and perhexiline not only inhibited the release of intracellular Ca2+ but also blocked the inflow of extracellular Ca2+.