中性粒细胞在大鼠急性重症胰腺炎肺损伤中的作用机制

目的:探讨急性重症胰腺炎(ASP)合并急性肺损伤时肺泡灌洗液中性粒细胞(PMN)凋亡和坏死的发生规律及可能涉及的作用机制.方法:选取雄性SD大鼠48只,分为ASP实验组(24只)、对照组(24只).实验组大鼠穿刺胰胆管并注入35g/L牛磺胆酸钠制作ASP大鼠模型,分别在制模后3,6,12 h剖杀,于预定时相取支气管灌洗液,密度梯度离心分离PMN,用流式细胞仪测定PMN凋亡、坏死比例,同时测定乳酸脱氢酶(LDH)含量、肺通透指数.结果:ASP组大鼠肺灌洗液中PMN存活细胞比例增加(P＜0.01),凋亡延迟.同时,肺灌洗液LDH明显升高(P＜0.01),肺通透指数显著增加(P＜0.01).结论:ASP合并急性肺损伤时,PMN凋亡延迟,造成PMN持续处于激活状态及毒性内容物的持续释放,与急性肺损伤密切相关.

Experimental study on PMN in acute severe pancreatitis with lung injury

AIM: To study the apoptosis and necrosis of polymorphonuclear neutrophils (PMN) from bronchoalveolar lavage fluid in acute severe pancreatitis (ASP) and to discuss the related mechanism. METHODS: Forty-eight male SD rats were divided into 2 groups (ASP group and control group). ASP model was established by injecting with 35 g/L taurocholic acid into the biliopancreatic duct. Both groups were sacrificed at 3, 6 and 12 h with 8 rats at each time point. At scheduled time, bronchoalveolar lavage fluid was drawn and PMNs were then obtained by gradient density gradient centrifugation method. The ratio of apoptosis and necrosis of PMN was assayed by flow cytometry and LDH as well as index of lung permeability were measured. RESULTS: In ASP group, the survival ratio of PMN increased and apoptosis of PMN was delayed. The level of LDH in bronchoalveolar lavage fluid and the index of lung permeability also increased. CONCLUSION: The delay of PMN apoptosis leads to persistent activation and leakage of toxic contents of PMN, which are closely associated with lung injury