Discussion The Protective Effect Of Low Molecular Weight Heparin In Smoke Inhalation Injury In Rats' Model

Objective:To investigate the potential beneficial effects of low molecular weight heparin (LMWH) in rats with smoke inhalation injury. Drugs were infused in their airways. It may be provid a useful theory and safe method for clinical treatment in smoke inhalation injury.Methods:Forty rats were divided randomly into four groups (n=10), normal control group (C group),smoke inhalation injury group (I group),low-dose group LMWH (L group) and high-dose group LMWH (H group). Normal sodium as a placebo was used in C group and I group, LMWH was instilled into the rats'trachea in L group (25 U/ml) and H group (50 U/ml). BrdU (100mg/kg) was intraperitoneal injected after 8 hours. All of the rats being sacrificed at 48h after smoke inhalation injury. Lung was checked for moisture and arterial blood was collected from the rats to determined the levels of tumor necrosis factor-α(TNF-α) and the interleukin-6 (IL-6). And estimate LMWH on airway epithelial cell proliferation through observing immunohistochemical staining of BrdU. The pathological changes and proliferation of pulmonary epithelial cells in lungs were also examined under an optical microscope.Results:Under the microscope, the lungs of rats in L group and H group were observed to have diffused alveolar septum thickening, spotty hemorrhage and more inflammatory granulocytes, but the histopathological changes were less than I group. Compared with the C group, the pulmonary edema, the levels of TNF-αand IL-6 were found to be higher in the I group,L group and H group(P< 0.01). Compared with the I group, the pulmonary edema, the levels of TNF-αand IL-6 were found to be lower in the L group and H group(P<0.05). The proliferated pulmonary epithelial cells were found in the L group and H group were more than I group(P< 0.01). Both L group and H group had not obvious difference. There is no sign of bleeding can be found in both of L group and H group.Conclusion:Intratracheal instillation of LMWH can relieve pulmonary edema and inflammatory reaction after smoke inhalation injury, also promote the pulmonary epithelial cells proliferating. And it may be provid a useful theory and safe method for clinical treatment in smoke inhalation injury...