Figure 4.

Effects of clopidogrel (30 μM) on collagen (2.5 μg ml⁻¹) (A) and U46619 (1 μM) (B)-induced aggregation of acetylsalicylic acid (10 μM)-treated washed human platelets. Experiments were carried out in the absence and presence of apyrase (1 u ml⁻¹). The aggregation was assessed by measuring the maximum change of light transmission. Data are given as % of aggregation response induced by the respective agonists without clopidogrel (control=100%). (means±s.e.mean of n=4 independent experiments, ^*P<0.05 vs control, Student's t-test for paired data).