Low Molecular Weight Heparin On Chronic Obstructive Pulmonary Disease Rat Model Of Lung Tissue Matrix Metalloproteinase-9 And Tissue Inhibitor Of Metalloproteinase-1

OBJECTIVE To observe the effects of low molecular weight heparin in the expression of matrix metalloproteinases-9(MMP-9) and tissue inhibitors of metalloproteinase -1(TIMP-1) in the chronic obstructive pulmonary disease of lung tissue in Wistar rats model,then demonstrate the intervention mechanism for chronic obstructive pulmonary disease of low molecular weight heparin.METHODS Thirty Wistar rats were randomly divided into three groups as follows,ten rats for each group:(1) the control group:raised the rats in normal condition for forty days without any interference(2) the COPD model group:the COPD animal model was made by smoke inhalations and intratracheal instillations of lipopolysaccharide and injected normal saline(one time/day) as control;(3) the low molecular weight heparin group:model methods were the same as above,low molecular weight heparin(Fragmin) 150IU/kg was given by hypodermic injection(one time/day) for 40 days.To observe the three groups of blood gas and lung tissue histopathological changes,lung tissue of MMP-9/TIMP-1 expression was examined by immunohistochemistry.RESULTS pathological changes of the lung tissue of low molecular weight heparin group could significantly be lessen.Compared with COPD model group,the expression of MMP-9 and the ratio of MMP-9/TIMP-1 were significantly different(q=26.72,3.34, P＜0.01).CONCLUSION Low molecular weight heparin may regulate MMP-9/TIMP-1 expression;lessen the degradation of extracellular matrix in destruction of extracellular matrix of alveolar wall when emphysema happened.It may be one of the important mechanisms for treatments of chronic obstructive pulmonary disease.