白蛋白对幼兔胎粪吸入综合征的保护作用及机制研究

目的:探讨白蛋白对胎粪吸入综合征的保护作用及机制。方法:将28只幼兔分为模型组(n=12)、白蛋白组(n=12)和正常对照组(n=4),建立幼兔胎粪吸入模型;在胎粪吸入后8、16、24小时计数支气管肺泡灌洗液(BALF)白细胞(WBC)、中性粒细胞(PMN),并采用放射免疫法测定肺组织匀浆液及BALF中IL-8含量,在显微镜下观察肺损伤的程度。结果:同对照组相比,模型组BALF中PMN和WBC数升高,肺组织匀浆液和BALF中IL-8含量明显升高,差异有极显著性(P<0.01),且肺组织病理改变明显。同对照组相比,白蛋白组上述指标呈现类似改变,而同模型组相应时间点相比,白蛋白组上述指标降低,差异有极显著性(P<0.01),肺损伤程度明显减轻。结论:幼兔胎粪吸入后,肺部产生明显的炎症反应,IL-8在胎粪吸入综合征的发生发展中占有重要的作用;白蛋白可通过减少IL-8的分泌,保护胎粪吸入所致的肺损伤。

Protective effect of albumin and its mechanism on meconium aspiration syndrome in immature rabbits

Objective:To investigate the protective effect of albumin and its mechanism on meconium aspiration syndrome in immature rabbits.Methods:Twenty-eight immature rabbits were randomly divided into three groups:model group (12 rabbits),albumin group (12 rabbits) and control group(4 rabbits).The animal model was established by endotracheal intubation imbuing 20% meconium (0.6 ml/kg).At 8.16.24 hours after instillation,the number of white blood cells(WBC),polymorphonuclear neutrophils(PMN)in bronchoalveolar lavage fluid (BALF)was calculated respectively:the level of IL-8 in lung tissue and BALF was measured by radioimmunoassay;and the pathological changes of lung tissues were observed under microscope. Results:Compared with control group.WBC,PMN,IL-8 were significantly increased in model group(P<0.01).The pathological changes of lung tissues were obvious.These variables of albumin group were similar with control group at every detecting point;compared with model group however,these variables were significantly decreased along with a slight pathological change of lung tissues.Conclusion:Aspirating meconium could induce remarkable pulmonary inflammatory response in immature rabbits.IL-8 may play an important role in the development of MAS.Albumin could protect lung injury resulting from meconium aspiration through retarding the production of IL-8 in lung tissues.