RESUMO
Objective To evaluate the effect of doxofylline on pulmonary inflammatory response induced by mechanical ventilation in rats with chronic obstructive pulmonary disease (COPD).Methods Thirty adult male Sprague-Dawley rats,aged 8 weeks,weighing 200-250 g,were divided into 3 groups (n=10 each) using a random number table method:control group (C group),COPD group and doxofylline group (Dox group).Rats were fed in normoxia for 2 months,and normal saline 0.2 ml was injected into the trachea on 1st and 30th days in C group.Rats were exposed to cigarette smoke for 30 min every day,lasting for 2 months,and lipopolysaccharide 200 μg (0.2 ml) was injected into the trachea on 1st and 30th days in COPD and Dox groups.Two months later,rats in each group were anesthetized,tracheally intubated,and then mechanically ventilated.Doxofylline 50 mg/kg was intravenously injected immediately after intubation in Dox group,and the equal volume of normal saline was given instead in C and COPD groups.Pulmonary specimens were taken after 120 min of mechanical ventilation for examination of pathological changes and for determination of wet/dry weight ratio (W/D ratio) and tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) contents (by enzyme-linked immunosorbent assay).Results No significant pathological change of lung tissues was found in C group,and COPD pathological changes were observed in COPD and Dox groups.Compared with C group,the W/D ratio and TNF-α level were significantly increased,and the IL-10 level was decreased in COPD and Dox groups (P＜0.05).Compared with COPD group,the W/D ratio and TNF-α level were significantly decreased,and the IL-10 level was increased in Dox group (P＜0.05).Conclusion Doxofylline can reduce the pulmonary inflammatory response induced by mechanical ventilation in rats with COPD.