Endogenous peroxynitrite mediates lipopolysaccharide-induced injury in cultured pulmonary artery endothelial cells

This study, using cultured bovine pulmonary artery endothelial cells (BPAECs), was undertaken to investigate the roles of endogenous ONOO(-) in LPS-caused injury in endothelial cells. The fluorescent intensity of nitrotyrosine (NT), a specific marker of ONOO(-) generation, in BPAECs represented the content of endogenous ONOO(-) generation. The fluorescent intensity of NT and the number of NT positive cells were detected with flow cytometry (FCM), and the percentage of NT positive cells was calculated. The results are as follows. (1) LPS (1, 5 and 10 microg/ml) caused a marked increase in fluorescent intensity of NT in a dose-dependent manner, which was significantly increased compared to the vehicle group (P