Phospholipose A₂ Activation mediate neutrophil apoptosis

Objective: To demonstrate the role of phospholipase A₂ activity （PLA₂） on the apoptosis of neutrophiles. Methods: The effect of PLA₂ activity on neutrophil apoptosis was investigated by light, electron microscopy, DNA agarose electrophoresis and flow cytometry analysis. Results: The results showed that the apoptosis of neutrophiles was promoted by the treatment of 1 μg/ml LPS and 1 μm A₂₃₁₈₇, in 6 hours and 12 hours respectively. The apoptosis of neutrophil was markedly delayed by a PLA₂ inhibitor, 4 bromophanacyl bromid （p BPB 0.01～1 mM）. Chloroquine, another PLA₂ inhibitor or SR_27417A, a PAF receptor antagonist, were found without such an effect as p BPB on neutrophil apoptosis. Conclusion: Results suggested that the neutrophile apoptosis may be promoted by phospholipase A₂ activation, but this process may not be related with PAF, one of the important metabolites of PLA₂.