Active oxygen formation in alveolar macrophage and pulmonary tumorigenesis

Glycerol enhances pulmonary tumorigenesis in mice treated with 4-nitroquinoline 1-oxide (4NQO). In order to evaluate factors that contribute to the enhancing effect of glycerol on 4NQO-induced pulmonary tumorigenesis, we selected alveolar macrophage (AM) as a source of active oxygen formation in the lung and investigated the effects of glycerol on active oxygen formation in AMs treated with 4NQO. AMs were stimulated with opsonized zymosan, and active oxygen formation in AMs was examined after stimulation. Continuous glycerol treatment within 4 weeks after 4NQO injection has no influence on the capacity of active oxygen generation in AMs (expressed as maximum count of chemiluminescence) and the total amount of active oxygen generation in AMs (expressed as total count of chemiluminescence). These results suggest that active oxygen formation in AMs does not contribute to enhance 4NQO-induced pulmonary tumorigenesis in mice treated with glycerol.