Objective:To investigate the changes of leukotriene B4(LTB4)、15-hydroxyeicosatetraenoic acid(15-HETE)in lung of an animal model with chronic obstructive pulmonary disease(COPD)

and the effects of ipratropium.Methods:Thirty-six male Wistar rats were randomized into three groups

Group A(normal controls

group B(COPD)

group C(smoking+ipratropium)

with 12 rats in each group.Group C receiving inhaling ipratropium 0.025%10ml and once a day for 23 days.Pulmonary functions of the rats were assessed

concen-trations of LTB4 15-HETE in lung tissue were measured by RP-HPLC.Results:The lung functions of FEV0.3/FVC%in COPD rats declined obviously(P<0.001)

While LTB4、15-HETE concentrations in lung tissue and lung functions of Ri、Re increased significantly as compared with the normal controls(P<0.001

P<0.05).Treatment with ipratropium Obviousely increased the levels of LTB4 and 15-HETE in lung tissue of the COPD rat(sP<0.001).However ipratropium had little effect on FEV0.3/FVC%、Ri and Re(P>0.05). Conclusion:Our results suggest that LTB4 and 15-HETE are involved in airway inflammation in COPD.Ipratropium is effective in decreasing the levels of LTB4 and 15-HETE in lung tissue of COPD rats

and attenuating inflammatory changes of airways.