Involvement of intracellular Ca2+ in chemotaxis and metabolic burst by neutrophils: the use of antagonists of intracellular Ca2+.

The effect of TMB-8, quin2, chlortetracycline, chlorpromazine and prenylamine on two neutrophil functions - chemotaxis towards fMLP and metabolic burst activated by PMA or fMLP - was compared. All drugs inhibited both functions in the absence of extracellular Ca2+. The inhibitory effect of all drugs on chemotaxis, and the effect of TMB-8, quin2 and chlortetracycline on the metabolic burst was antagonized by extracellular Ca2+. There were differences between inhibition of chemotaxis and the metabolic burst, and between inhibition of PMA activated and fMLP-activated metabolic burst. The results are consistent with the view that intracellular Ca2+ is required in chemotaxis, and in PMA or fMLP activated metabolic burst, but that the role of Ca2+, or the location where Ca2+ is derived from, is different and depends on function and the type of activator.