Effect of verapamil on platelet surface ultrastructure and calcium content.

The effect of verapamil on the surface ultrastructure and calcium content of human platelets was studied by scanning electron microscopy and X-ray microanalysis. The results showed that the drug prevents platelet pseudopodia formation and causes a dose-dependent inhibition of platelet calcium concentration. The significance of these findings in the explanation of the inhibitory effect of verapamil on platelet aggregation is discussed.