Effects Of Deferoxamine On Pulmonary Surfactant And Antioxidant Enzymes In Rats With Lung Injury Induced By Short-term Hyperoxia

Objective:To investigate the effects of deferoxamine on pulmonary surfactant and antioxidant enzymes in rats with lung injury induced by short-term hyperoxia.Methods:Twenty-four sprague dawley rats?weighing 180-220g?were randomly divided into 3 groups?n=8/group?:mechanical ventilated with normoxia group?group MV?,with hyperoxia group?group HMV?,or with hyperoxia+DFO group?group HMV+DFO?.Tracheotomy and catheterization were carried out under general anesthesia.The rats in group MV were ventilated with air?FiO₂=21%?,groups HMV and HMV+DFO were ventilated with oxygen?FiO₂=90%?for 4 h.Meanwhile,groups MV and HMV were infused normal saline?1 ml/h?via tail vein,group HMV+DFO were infused the same volume of DFO?200 mg/kg,1 ml/h?intravenously.The left carotid artery was punctured and cannulated under a sterile condition,and artery blood was taken for blood gas analysis at 2 h and 4 h of ventilation,to monitor arterial partial pressure of oxygen?PaO₂?and partial pressure of carbon dioxide?PaCO₂?,adjust respiratory rate and calculate oxygenation index?OI?.The bronchoalveolar lavage fluid?BALF?was prepared in left lung after 4 h of ventilation.The right lung was taken to make tissue homogenate,measure the wet/dry weight?W/D?ratio,make pathological section and the injury level was scored.The content of pulmonary surfactant protein C?SP-C?,pulmonary surfactant protein D?SP-D?,the activity of glutathione reductase?GR?and xanthine oxidase?XOD?were detected in BALF and lung homogenate by ELISA,respectively.Results:The result of blood gas analysis show:PaO₂ in groups HMV and HMV+DFO were significantly higher than those of the group MV?P<0.05?,and the OI were significantly lower.While PaO₂ and OI between groups HMV+DFO and HMV did not differ significantly.Compared with group MV,the content of SP-C,SP-D and the activity of GR in groups HMV and HMV+DFO were lower?P<0.05?,the activity of XOD,W/D and pathological evaluation were much higher?P<0.05?;Compared with group HMV,the content of SP-C,SP-D and the activity of GR in group HMV+DFO were higher?P<0.05?,the activity of XOD,W/D and pathological evaluation were lower?P<0.05?.Conclusions:Mechanical ventilation with hyperoxia for 4 h could induce oxidative injury of the lungs,accompanied by a dramatic reduction in the concentrations of SP-C and SP-D.DFO infusion has an effect of increasing SP-C,SP-D content and alleviating lung injury,and the mechanism is related to the increased GR and decreased XOD activity.