Production of nitric oxide (NO) in response to bacterial lipopolysaccharide (LPS) was investigated using cultures of mouse peritoneal exudate cells (PEC) and the macrophage cell line . In the presence of anti-(interferon-c) (IFN-c), NO production was markedly suppressed in the PEC culture but not in the culture. In the PEC culture, LPS induced both IFN-cproduction and activation of IFNresponse factor-1, which leads to the gene expression of inducible NO synthase, but neither was induced in the culture of cells
