A study of the effects of indomethacin, flufenamate and salicylate on the localization of intracellular calcium in rabbit neutrophil polymorphs using an antimonate staining method.

An antimonate staining technique was used to localize intracellular calcium in rabbit peritoneal neutrophil polymorphs. When calcium was added to a previously calcium-free extracellular medium neutrophils showed a slight loss of intracellular stainable calcium after 1 h incubation. There was a significant increase in the number of damaged cells and a slight increase in degranulation. Indomethacin (5 X 10(-5)M and 8 X 10(-4)M), both in the absence and the presence of extracellular calcium, enhanced the loss of stainable calcium, and at 37 degrees, increased the amount of damage, but increased degranulation only at the higher concentration and in the presence of calcium. Indomethacin may act as a membrane labilizer. Salicylate (2.5 X 10(-3)M and 1 x 10(-2)M at 37 degrees) slightly decreased the loss of intracellular calcium in the presence of extracellular calcium and, in the absence and presence of calcium and at the higher concentration, decreased degranulation and decreased the amount of damage. Salicylate may act as a membrane stabilizer. Flufenamate (3 x 10(-5)M and 2.4 x 10(-4)M) showed variable effects.