Extracellular calcium and magnesium interfere differently with actin polymerization in human and rabbit neutrophils

This study attempts to elucidate, in man and rabbit neutrophils, the relevance of extracellular Ca2+ and Mg2+ to actin polymerization induced by fMLP, a chemotactic peptide. The presence of as little as 0.2 mM divalent ions in the cell suspending medium inhibits the actin polymerization in rabbit neutrophils, and partially reduces it in human neutrophils.