The Effect of Sulphydryl and Enzyme Inhibitors on Platelet Aggregation in Vitro

Summary

The glycolytic enzyme poisons potassium cyanide, sodium fluoride, and monofluoroacetate do not inhibit platelet clumping. The sulphydryl inhibitors, n-ethyl maleimide and p-hydroxymercuribenzoate, inhibit platelet aggregation produced by ADP, ATP, nor-adrenaline, 5HT, thrombin and connective tissue extract. This inhibitory activity is counteracted by 1-cysteine. These results suggest that platelet thiol groups are involved in the platelet adhesion occurring during aggregation.

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