Ascorbate-enhanced nitric oxide (NO) production in lipopolysaccharide (LPS)- and interferon-gamma (IFN-gamma)-activated macrophage J774.1 cells through the inducible nitric oxide synthase (iNOS) pathway. The iNOS gene was synergistically induced by LPS and IFN-gamma. The inductive mechanism of ascorbate on the iNOS gene was studied by examining the degradation of I kappa B alpha by Western blot...