Involvement of nitric oxide on the peritoneal neutrophil influx induced bystaphylococcal enterotoxin B in mouse

In this study, the role of nitric oxide (NO) on neutrophil migration induce d by staphylococcal enterotoxin B (SEB) in the mouse peritoneal cavity was investigated. The NO synthase inhibitors L-NAME and aminoguanidine, as well as dexamethasone, markedly reduced SEE-induced neutrophil influx. In mice with an increased population of peritoneal macrophages, the inhibition of S EE-induced neutrophil influx by these agents was significantly lower. The i n vivo treatment with aminoguanidine inhibited only the iNOS activity, wher eas L-NAME inhibited both the cNOS and iNOS activities. In conclusion, NO m odulates the neutrophil migration in response to SEE through the activity o f an iNOS isoform. (C) 2001 Elsevier Science Ltd. All rights reserved.