Effects of diesel exhaust particles on airway hyperresponsiveness and immunologic index in rats

ObjectiveTo investigate the effects of disesel exhaust particles in air pollutants on airway hyperre sponsiveness and immunologic index in rats with asthma.MethodsSixty Wistar rats were rendomly dividedinto 6 groups.Grup A was control group.Group B was animal model group which was ovalbumin(OVA)sensitized challenged.Group C,D,E,F were challenged with 3% OVA and then exposed to diesel exhaust particles(DEP)for one to four weeks.The levels of IgE,interleukin 5(IL-5)and interferon(IFN-γ)of the lung tissue were detected by ELISA.ResultsThe airway hyperre sponsiveness of group B increased more than group A.Group B was significantly different from group E and F(F=156.186,P<0.01).Increase of airwag resistance was related with the time of DEP exposure(r=0.948,P<0.01).The concentration of IgE was significantly different between group A and B(F=2.490,P<0.01).The expression of IL-5 in lung tissue gradually increasedin group C.The expression of IL-5 in group B was significantly different from that of group C and E(F=4.263,P<0.01).The expression of IFN was not significantly different among the groups(F=1.193, P>0.05).ConclusionExposure to diesel exhaust particles might exacerbate airway hyperrespon siveness andinduce airway in flammation caused by IL-5 increase in the rats of asthma model.