Objective To investigate the effects of lipoxin A4 on store-operated calcium channel (SOC) and production of reactive oxygen species in macrophages induced by hpopolysaccharide (LPS).Method Macrophages were randomly assigned Io one of the following six groups:control group,LPS group,Thapsigargin group,lipoxin A4+LPS group,lipoxin A4+Thapsigargin group,2-Aminoethoxydiphenylborate+Thapsigargin group.The intracellular[Ca2+]iwas analyzed by eonfoeal laser microscopy.The production of reactive oxygen specips(ROS) was assayed by flow cytometry.Results LPS increased intracellular[Ca2+]i and reactive oxygen species in a dose-dependent manner.Lipoxin A4 suppressed approximately 75% of the Ca2+ ertry signal induced by thapsigargin and suppressed approximately 93% of the Ca2+ entry signal induced by LPS.The increase in intracellular[Ca2+]i was associated with increased ROS production which was abolished in the presence of lipoxin A4.Conclusions These findings indicate that the LPS-indueed intracellular[Ca2*]i increase depends on the Ca2+entry through SOC channel,and lipoxin A4 inhibits Ca2+ influx and ROS production through SOC channel in ratine maerophages induced by LPS.