OBJECTIVETo explore the in vitro anti-platelet effects of Ginsenoside -2A,a purified extract from Panax notoginseng.

METHODSPlatelet rich plasma (PRP) was prepared routinely from venous blood samples of patients with essential hypertension and normal persons. PRP was incubated with different concentrations of Nifedipine, Ginsenoside-2A ,and SK&F96365. Maximal platelet aggregation rate[ PAG (M) ] induced by 2 micromol/L ADP was taken as the observed index. Five-minute PAG( M) was determined for 5 consecutive times.

RESULTS(1) PAG (M) in essential hypertension group was 0. 89 +/- 0. 06, which was higher than that in the normal group (0. 68 +/-0. 07 ) with significant difference (P <0.01). (2)Nifedipine of two concentrations (10 p.mol/L,20 pVmol/L) had no effect on PAG(M) in either essential hypertension group or normal group(P >0. 05). (3)Different concentrations of SK&F96365 (2.5 micromol/L,5 micromol/L,10 micromol/L and 20 micromol/L) could inhibit the PAG(M) in essential hypertension group; (4) Differen concentrations of Ginsenoside -2A (2. 5 micromol/L, 5 micromol/L, 10 micromol/L and 20 micromol/L) could inhibit PAG ( M) in essential hypertension group; three concentrations of Ginsenoside -2A (5 micromol/L, 10 micromol/L, 20 micromol/L) could inhibit the PAG(M) in the normal group (all P <0.05).

CONCLUSIONPlatelet aggregating function in essential hypertension patients was obviously higher than that in the normal persons and platelets was in the high reactive status. Nifedipine had no inhibitive effect on platelet aggregation. SK&F96365 could inhibit the platelet aggregation. Ginsenoside-2A could inhibit platelet aggregation, and had the definite anti-platelet action.