The effect of Trimepranol on thrombocyte function and histamin release in the rat.

Trimepranol a beta adrenergic blocking drug released serotonin from rat isolated and plasma-rich thrombocytes in vitro. The release was time- and dose-dependent. With the same concentrations this drug inhibited the histamine release from isolated rat mast cells. Aggregation of isolated or plasma-rich thrombocytes induced by ADP was inhibited by Trimepranol. The inhibition was dose, time dependent and reversed by calcium ions.