[Endotoxin-induced generation of peroxynitrite in bovine pulmonary arterial endothelial cells].

AIM

To explore the significance of bovine pulmonary arterial endothelial cell (BPAEC) to produce peroxynitrite (ONOO-).

METHODS

The contents of nitrotyrosine (NT), a marker of ONOO- generation in vivo,were quantitatively measured with flow cytometric and immunofluorescent technique in cultured BPAEC induced by lipopolysaccharide (LPS), a major component of bacterial endotoxin. In addition, effect of ONOO- on micromorphologic features of BPAEC was observed.

RESULTS

LPS caused significant increase of NT in BPAEC in a dose-dependent manner, which was in part reversed by aminoguanidine, a selective inhibitor of inducible nitric oxide synthase. Exposure of BPAEC to exogenous ONOO- resulted in the cellular retro-contraction with diminished cellular body and increased width of cellular junction.

CONCLUSION

LPS may induce the ONOO- formation of BPAEC. Endothelial cell-derived ONOO- may mediate the deleterious effect of LPS on BPAEC per se.