Abstract: The effects of 1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino)propane hydrochloride(DDPH)and verapamil on cytosolic free calcium concentratiOn of rabbitplatelets were investigated.The results showed that the elevation of cytosolic free calciumconcentration(Ca²⁺i)of rabbit platelets following ionophore A23187 was significantly inhibited byDDPH and verapamil.The rates of inhibition with DDPH and verapamil were 58 % and 78 %,respectively,with no significant difference between the two groups(P>0.05).