A morphological study of the effects of indomethacin, flufenamate, salicylate and calcium ions on rabbit peritoneal neutrophil polymorphs.

Rabbit peritoneal neutrophil polymorphs have been examined by transmission electron microscopy to determine the effects of removing and replacing extracellular calcium. Degranulation, disruption of the cell membrane and vesiculation are all more marked in the presence of calcium than in its absence. Cooling the cells to 4 degrees has a protective effect. The addition of indomethacin, flufenamate or salicylate to a calcium-free incubating medium decreases degranulation, protects the membrane and reduces vesiculation, particularly at 4 degrees. When extracellular calcium is replaced at 37 degrees indomethacin and salicylate slightly reduce the amount of degranulation; flufenamate and salicylate significantly reduce the signs of damage. Higher concentrations of indomethacin and flufenamate cause considerable degranulation and damage. When extracellular calcium is present in the incubating medium throughout, the addition of indomethacin, flufenamate or salicylate shows varying effects. High concentrations of all these drugs, however, cause extensive degranulation and damage.