RESUMO
<p><b>OBJECTIVE</b>To investigate the effect of paraquat (PQ) on reactive oxygen species (ROS) and neutrophil apoptosis and its possible signal transduction pathways.</p><p><b>METHODS</b>Cultured neutrophils were treated with different concentrations of PQ for 6-24 h. The apoptosis rate of neutrophils and ROS content were determined by flow cytometry. The exoressions of nuclear factor kappa B (NF-κB) and Caspase 3 were detected by Western blot. These parameters were checked again after NF-κB and Caspase 3 antagonist were applied.</p><p><b>RESULTS</b>PQ could boost ROS generation and depress neutrophil apoptosis significantly. At the same time PQ could enhance the expression of NF-κB and inhibit the expression of Caspase 3. These effects could be reversed by ROS inhibitor diphenyleneiodonium (DPI) and NF-κB inhibitor pyrrolidinedithiocarbamate (PDTC).</p><p><b>CONCLUSION</b>PQ is a potent inducer of ROS and can inhibit neutrophil apoptosis by activating NF-κB and surpressing Caspase 3 activity.</p>