摘要
目的：研究蛋白酶 抗蛋白酶失衡在内毒素诱发急性肺损伤（ＡＬＩ）兔模型中的作用。方法：成年健康新西兰大白兔１６只经麻醉、气管切开插管后给予机械通气。随机分成２组（每组８只）：即内毒素（ＬＰＳ）致ＡＬＩ模型组（ＬＰＳ组）和生理盐水对照组（ＮＳ组）。监测动脉血氧分压（ＰａＯ２ ）、动脉血压（ＢＰ）、外周血白细胞数（ＷＢＣ）、气道峰压（Ｐｐｅａｋ ）、静态总呼吸顺应性（ＴＲＣ）和肺内动静脉分流（Ｑｓ／Ｑｔ）等指标的变化；比较实验８ 小时后血浆α１ 抗胰蛋白酶（α１ ＡＴ）含量和活性、支气管肺泡灌洗液（ＢＡＬＦ）中总蛋白（ＴＰ）含量、中性粒细胞弹性蛋白酶（ＮＥ）样活性、α１ ＡＴ活性、白介素 ８（ＩＬ ８）、肿瘤坏死因子 α（ＴＮＦ α）、总磷脂（ＴＰＬ）、饱和磷脂酰胆碱（ＤＳＰＣ）含量及肺湿重与干重比（Ｗ／Ｄ）的差异。结果：与基础值相比，静注ＬＰＳ后ＰａＯ２ 下降，氧合指数＜ ２６．６７ ｋＰａ（１ ｋＰａ＝ ７．５ ｍ ｍ Ｈｇ），ＴＲＣ下降＞ ５０％ ，肺内动静脉分流增加＞ ２５％ ；与ＮＳ组相比，血浆α１ ＡＴ含量增高但活性下降，外周血白细胞减少，而ＢＡＬＦ中ＴＰ含量、ＮＥ样活性、ＩＬ ８ 和ＴＮＦ α浓度增加，α１ ＡＴ活性、ＴＰ?
Objective:To assess the role of proteaseantiprotease imbalance in the pathogenesis of acute lung injury(ALI) in rabbits induced by endotoxin.Methods:16 adult healthy New Zealand rabbits were anaesthetized,tracheotomized and mechanically ventilated,then randomly divided into two groups ( n =8):infusion of Escherichia coli endotoxin 〔lipopolysaccharide(LPS)500 μg/kg,group LPS〕and infusion of saline (group NS).PaO 2,peripheral leukocyte count,airway pressure and s/s/t were recorded for 8 hours.The plasma concentration and activity of α 1antitrypsin(α 1AT) were determined.Then all animals were sacrificed and the bronchoalveolar lavage fluid (BALF) was collected for measurement of concentrations of total protein (TP),interleukin8(IL8),tumor necrosis factor(TNFα),total phospholipids(TPL) and desaturated phosphatidylcholine (DSPC),the activities of neutrophil elastase(NE) and α 1AT.The wettodry lung weight ratio (W/D) was measured.Results:After infusion of endotoxin,it was observed that PaO 2,peripheral leukocyte count,total respiratory compliance progressively decreased and P peak and s/t increased compared with the baseline values.In contrast to group NS the increased plasma concentration but reduced activity of α 1t increased compared with the baseline values.In contrast to group NS the increased plasma concentration but reduced activity of α 1AT were found in LPS group.In the BALF,the activities of α 1AT,TPL,DSPC/TPL were lower than those in group NS,but the concentrations of albumin,IL8,TNFα,the activity of NE and the ratio of W/D were higher than those in group NS.Conclusions:The imbalance between proteases and antiproteases might play an important role in the pathogensis of ALI.
出处
《中国危重病急救医学》
CAS
CSCD
2000年第1期10-14,共5页
Chinese Critical Care Medicine
基金
卫生部科技基金!资助项目(98 1 150)
上海医科大学硕士研究生课题
关键词
肺损伤
急性
弹性蛋白酶
内毒素
Α1-AT
acute lung injury
α 1antitrypsin
neutrophil elastase
rabbits
endotoxin
