Quartz and Chrysotile Up regulate Nitric Oxide and Nitric Oxide Synthase Activity in Rabbit Alveolar Macrophages

In order to explore the role of nitric oxide(NO)and nitric oxide synthase(NOS)in dust(quartz and asbestos)-caused diseases,rabbit avleolar macrophages collected by Myvirk method were cultured in vitro.NO₂^-/NO₃^-,the stable oxide formation of NO,in the culturing supernatants of TiO₂-,quartz-and chrysotile-treated AMs was measured by nitrate reductase reaction method,and NOS activity was measured with color reaction method(enzyme-substant reaction).The results showed that with the increase of dust concentration,(1)AM mortality increased in both quartz and chrysotile group,the effect of different dust was different:chrysotile>quartz>TiO₂.(2)In both quartz and chrysotile groups,NO₂^-/NO₃^- increaed with dose-response relationship(P<0.05);at the higher dose group,NO in both groups was higher than that of TiO₂ group respectively,but there was no difference in quartz and chrysotile group(P>0.05).(3)NOS activity elevated in quartz and chrysotile groups,but in 100,200μg/ml chrysotile group,the NOS activity decreased,which was maybe result from AM mortality increasing.(4)The change of NO was agreement with the change of NOS activity in quartz-and chrysotile-exposed AMs.It was suggested that NO and NOS were maybe potential role in quartz-and chrysotile-related diseases.