Effects of atorvastatin on ADP-, arachidonic acid-, collagen-, and epinephrine-induced platelet aggregation

OBJECTIVE: Atorvastatin reduces the incidence of cardiovascular events. However, the effects of atorvastatin on platelet aggregation are unknown. METHODS: Blood samples were obtained from 126 healthy volunteers. Prepared isolated platelet suspensions were adjusted with saline to three different concentrations of 100 × 10(9), 300 × 10(9), and 600 × 10(9) platelets/L. Platelet samples were incubated with atorvastatin (10(−7 )mol/L, 10(−6 )mol/L or 10(−5 )mol/L), and stimulated with ADP (10 µmol/L), arachidonic acid (0.5 mmol/L), collagen (2 µg/mL), and epinephrine (1 mg/mL). The maximal amplitude of aggregation and the curve slope were measured by electric impedance aggregometry. RESULTS: Atorvastatin inhibited platelet aggregation at moderate (300 × 10(9)/L) and high (600 × 10(9)/L) concentrations. However, an inhibitory effect of atorvastatin at low concentrations (100 × 10(9)/L) was not observed. CONCLUSIONS: The study shows that atorvastatin inhibits platelet aggregation in vitro, and this inhibitory effect is related to platelet concentrations.