Using Fura-2AM microfluorimetry it was shown for the first time that 5-lipoxygenase specific inhibitors zileuton and caffeic acid significantly inhibit Ca2+ responses, induced by neuroleptic trifluoperazine, in macrophages. The results suggest the involvement of 5-lipoxygenases and/or products of 5-lipoxygenase pathway of arachidonic acid cascade in the effect of trifluoperazine on intracellular Ca2+ concentration in macrophages.