Effects of econazole and clotrimazole on TXB2 and PGE2 production in calcimycin-stimulated neutrophils and arachidonic acid-stimulated platelets

The effects of econazole and clotrimazole which are used as antifungal agents, on TXB2 and PGE2 production in calcimycin (A-23187)-stimulated rat pleural neutrophils and arachidonic acid (AA)-stimulated washing rabbit platelets were examined by radioimmunoassay. Econazole and clotrimazole 0.05-100 mumol.L-1 inhibited TXB2 production both in rat pleural neutrophils and in rabbit platelets with a dose-dependent manner. The most potent inhibition was found in rabbit platelets. At the concentration of 50 mumol.L-1, econazole and clotrimazole were sufficient to inhibit TXB2 production in rabbit platelets by up to 99% and 98% respectively. Econazole and clotrimazole 0.05-5 mumol.L-1 also increased PGE2 biosynthesis in rabbit platelets. But econazole and clotrimazole 50 mumol.L-1 reduced the PGE2 production in rabbit platelets to 11% and 37% of the amounts of 5 mumol.L-1 econazole and clotrimazole respectively. The results suggest that econazole and clotrimazole at lower concentration may have a selective inhibitory effect on thromboxane synthetase, at higher concentration they also inhibit cyclooxygenase.