Therapeutic effects of combined LMWH and UTI on pulmonary fibrosis induced by acute Paraquat poisoning in rats

Objective To investigate the preventive effects of low molecular weight heparin(LMWH) combined with ulinastatin(UTI) on the acute Paraquat poisoning in rats with pulmonary fibrosis.Methods Fifty five SD rats were divided into control group(group A),pmonary fibrosis group(group B) and prevention group(group C).Pulmonary fibrosis(group B and C) was induced by feeding the rats with Paraquat after fasting for one hour(75 mg/kg),and group A received normal saline.Then the rats in group C received low molecular weight heparin(1 000 U/d,subcutaneous injection) and UTI(10~5 U,peritoneal injection) for 14 days.Group A and B received normal saline(0.2 ml/d).Five rats in each group were killed on the 1th,3th,7th,14th and 28th days,respectively.Specimens from lung tissue and serum were collected.HE staining of lung tissues was prepared and the serum levels of transforming growth factor β1(TGF-β1) and matrix metalloproteinase 9(MMP-9) contents were measured.Results Serum level of TGF-β1 in group B was significantly increased at day-3(P0.01),serum MMP-9 was gradually increased in the first 7 days(P0.05),and was significantly higher(P0.01) at day-28.Level of MMP-9 in group C at the 7th day was decreased compared with group B(P0.05),and the level was significantly difference at day-28(P0.01).Level of TGFβ1 in group C at day-14 was decreased and the value was significantly different from group B at the day-14(P0.01).Alveolar wall thickness was increased in the B group during the early phase after making a model.Infiltration of inflammatory cells,capillaries congestive,and edema were obvious at day-14.Lung surface ulcer was found,and alveolar interval into fiber mother cells,Muscle fiber cell hyperplasia and alveolar collapsion could be seen under electron microscope.When the C group has alveolar wall capillaries congestive,inflammatory sexual cell infiltration more model group light,lung fiber of degree also more by reduce.Conclusion Low molecular weight heparin combined with ulinastatin may reduce TGF-β1 and MMP-9,thereby reducing fibrosis in rats.