Dust and LPS Induced Stimulation of Nitrite and Nitrate Release in Bovine Alveolar Macrophages

Abstract

Several types of cells have been demonstrated to generate nitric oxide using the guanidino group of L-arginine. In peritoneal macrophages and monocyte cell lines this pathway is non-constitutive (Stuehr and Marietta, 1987). The activation of the nitric oxide synthesis during macrophage development differs from that of the cytokine synthesis (Hauschildt et al.,1990) and is independent from the respiratory burst during phagocytosis (Iyengar et al.,1987). Authentic nitric oxide gas causes the same pattern of cytotoxicity in L10 hepatoma cells as is induced by cytotoxic activated macrophages in vitro (Hibbs et al., 1988). Thus nitric oxide and its stable oxidation products nitrite and nitrate are thought to be involved in the cytostatic and killing properties of macrophages.