Effects of Panax notoginseng saponins on platelet aggregation in rats with middle cerebral artery occlusion or in vitro and on lipid fluidity of platelet membrane

The effects were examined of Panax notoginseng saponins (PNS) on platelet aggregation in vivo or in vitro and on lipid fluidity of the membrane. PNS (200 mg/kg i.p. x1 d or x3 d) significantly inhibited abnormal increases of platelet aggregation and platelet adhesiveness in rats subjected to permanent occlusion of the middle cerebral artery (MCAO). Platelet aggregation induced by ADP in vitro was also inhibited by PNS in a concentration-related manner. PNS could increase the fluidity of platelet membranes, The findings in this study suggest that the anticerebral ischaemic effect of PNS depends, at least partially, for its actions on blood platelets. (C) 1998 John Wiley & Sons, Ltd.