Effect of triflusal and other salicylic acid derivatives on cyclic AMP levels in rat platelets.

The effect of triflusal, acetylsalicylic acid (ASA), and of their principal metabolites 2-hydroxy-4-trifluoromethylbenzoic acid (HTB) and salicylic acid (SA), alone or combined with dypiridamole (DIP) and/or PGE1 on cyclic AMP levels in washed rat platelets (37 degrees C, 4 min), has been determined. DIP at 0.1 mM increased cyclic AMP levels by 25%. The effect of triflusal and HTB was significant at therapeutic concentrations of triflusal (1 mM: 36% increase) and HTB (0.5 mM: 37% increase). The effect of HTB was always greater than that of triflusal. ASA, at 1 mM and 5 mM, alone or combined with PGE1 was without effect. When 1 mM triflusal was combined with 0.1 mM DIP an increased effect was obtained (95%). ASA, at the highest concentration tested (5 mM), did not modify the DIP-induced increase of cyclic AMP levels.