The calcium ionophore ionomycin primes polymorphonuclear leukocytes (PMN) for increased superoxide production upon stimulation with the chemotactic peptide FMLP (Helman Finkel, T. et al. J Biol Chem 1987; 262: 12589-12596). In this investigation we assessed the effect of PMN priming with either alpha hemolysin (AH) or the calcium ionophore A23187, both of which increase intracellular calcium, on the oxidative metabolism of PMN (as measured by chemiluminescence) in response to secondary stimulation with FMLP. Both A23187 and AH priming increased the luminol-enhanced chemiluminescence in response to secondary stimulation with FMLP, indicating overstimulation of PMN oxidative metabolism. Additional experiments using lucigenin as chemiluminescence enhancer showed that A23187, but not AH priming of PMN, increased superoxide release in a manner similar to that reported for ionomycin. These results are discussed in reference to infectious processes involving hemolytic E. coli.

polymorphonuclear leukocytes; chemiluminescence; luminol; lucigenin; A23187; alpha hemolysin; FMLP