The Study Of UPA/uPAR/PAI-1 System In Pulmonary Tissue Of Rats With Smoking Induced COPD

Objective To investigate the state of urokinase type plasminogen activator system which includes urokinase type plasminogen activator(uPA) ,urokinase type plasminogen activator receptor(uPAR) and plasminogen activator inhibitor-1(PAI-1) in pulmonary alveoli disrict and airway district of rats by setting up rat model ofsmoking induced COPD, then discuss the effect of uPA/uPAR/PAI in pathogenesis ofCOPD.Methods 16 male Wistar rats were randomly divided into two groups: The normal control group and the COPD group. Rats in the COPD group were exoposed to cigarette smoke daily. At the end of three months, when COPD model was established, items below should be observed:(1)Observe the pathomorphological changes in pulmonary with microscope.(2)Total and differential cell counts in BALF were done.(3)The expression of uPA/uPAR/PAI in pulmonary alveoli disrict and airway district was observed by Streptavidin/Peroxidase immunohistochemistry technique.Results (1) The model group rats shared specific pathological features in trachea, bronchi and lung tissues with that of human chronic bronchitis and obstructive emphysema. The quantitative assay of morphology shows: Compared with the normal control group, MLI significantly increase, MAN significantly decreased (P<0.05 and P<0.05, respectively) in model group;internal diameter/external diameter significantly decreased (P<0.05), thick of airway/external diameter have no significantly differience(P>0.05). (2)TotaI and differential cell counts in BALF: Compared with normal group, totalwhite cell counts in BALF in COPD group significantly increase (P<0.01) ;. the ratioof neurophils significantly increase, (P<0.01) ;.the ratio of lymphocyte significantlydecreased (P<0.05); the ratio of monocyte-macrophage have no significantly differience (P>0.05).(3) uPA/uPAR/PAI in pulmonary tissue were maily expressed in inflamatory cell(including monocyte-macrophage^ neurophils and lymphocyte)^ alveolar epithelial celK airway epithelial cell, fibroblasto Compared with normal group, the count of poisitive cell expressing uPA/uPAR/PAI in both pulmonary alveoli disrict and airway district inCOPD group significantly increase, (P<0.01) ;.the expressing intensity of positive cell in both pulmonary alveoli disrict and airway district in COPD group significantly increase, (PO.01) .(4)Compared with normal group,the uPA/PAI-1 relative value of the count of poisitive cell in both pulmonary alveoli disrict and airway district in COPD group have no significantly differience (P>0.05); the uPA/PAI-1 relative value of expressing intensity of poisitive cell in both pulmonary alveoli disrict and airway district inCOPD group significantly increase, (P<0.01) .Conclusions(DCompared with normal group, the count and expressing intensity of poisitive cellexpressing uPA/uPAR/PAI in both pulmonary alveoli disrict and airway district inCOPD group significantly increase.(2)Compared with normal group,the uPA/PAI-1 relative value of expressing intensityof poisitive cell in both pulmonary alveoli disrict and airway district in COPD groupsignificantly increase,presenting a state of uPA superiority.