高碳酸血症对急性肺损伤氧自由基生成的影响  

Effects of hypercapnia on oxygen free radicals in acute lung injury models

作　　者：杨丽丽[1] 刘志[2] 戢新平[2] 刘刚[3] 关福兰[4] 

机构地区：[1]中国医科大学附属盛京医院风湿免疫科,沈阳110004 [2]中国医科大学第一临床学院急诊科 [3]中国医科大学呼吸疾病研究所 [4]中国医科大学药理学教研室

出　　处：《中华急诊医学杂志》2008年第4期361-365,共5页Chinese Journal of Emergency Medicine

基　　金：辽宁省教育厅高等学校科学研究项目（202013152）

摘　　要：目的观察高碳酸血症对兔急性肺损伤（ALI）模型是否具有保护作用，并观察其对ALI时氧自由基生成的影响，探讨高碳酸血症对ALI可能的作用机制。方法于中国医科大学药理学实验室将22只新西兰大白兔随机分为对照组（C组，n=6）、非高CO2通气组（N组，n=8）、高CO2（8％CO2）通气组（H组，n=8）。将动物气管切开，进行机械通气。N组和H组通过静脉注射油酸（0．1ml／kg）复制ALI模型。C组给予生理盐水（0．1ml／kg）。监测肺组织呼吸力学指标、血气分析指标的变化。继续机械通气至3h，将动物处死，取出心肺，检测肺组织中超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量，测定肺组织湿质量／干质量比、肺通透指数等指标并观察肺组织病理学改变。结果H组气道峰压显著低于N组，动态胸肺顺应性显著高于N组，动脉血氧分压H组明显高于N组（P〈0．05）。肺组织中MDA含量H组明显低于N组（P〈0．05）；SOD活性H组明显高于N组（P〈0．05）；肺湿质量／干质量比及肺通透指数H组明显低于N组（P〈0．05）。H组病理组织学改变较N组明显减轻。结论机械通气时吸入8％的CO2所致高碳酸血症对ALI动物模型有一定的保护作用，其机制可能与提高了肺组织中SOD活力，减轻了脂质过氧化有关。Objective To investigate the protective effects of hypercapnia on acute lung injury （ALI） in an model of rabbits in vivo, and to observe its effect on oxygen free radicals in the lung tissue in order to uncover the potential mechanisms. Method In the laboratory of pharmacology, China Medical Univercity, twenty-two healthy New Zealand white rabbits were randomly assigned to control group （Group C, n = 6） with the injection of normal saline （0.1 ml/kg）, and sixteen rabbits were injected with oleie acid （0. 1ml/kg） intravenously, and then were randomly diridod into normocapnia group （Group N, n = 8） and hypercapnia group （Group H, n = 8, FiCO2 = 8% ）. Then traeheostomy was performed, and the experimental animals were ventilated for 3 hours after oleie acid or sterile normal saline administration, lung mechanics, hemodynamics, blood-gas analysis were monitored. The rabbits were exsangninated, and the lungs and heart were taken out from the thorax. The concentration of supemxide dismutase （SOD） and malondialdehyde （MDA） in the lung tissue were assayed. Lung tissue wet/dry ratio and pulmonary permeability index were measured and histologie damage was assessed after three hours＇ mechanical ventilation. Results Peak airway pressure in Group H was significantly lower than that in Group N and the dynamic lung compliance was significantly higher than that in Group N （ P 〈 0.05）. PaO2 in Group H was significantly higher than that in Group N （ P 〈 0.05）. The concentration of MDA in the lung tissue in group H was significantly lower than that in Group N （ P 〈 0.05 ）, and SOD in group H was significantly higher than that in Group N （ P 〈0.05）. Lung tissue wet/dry ratio and pulmonary permeability in group H were significantly lower than that in Group N （ P 〈 0.05）. Histological tissus damage in Group N wassignificantly severer than that in Group H. Conclusions Hypercapnia induced by inhalation of high concentration of carbon dioxide （8%） plays protective role in

关 键 词：高碳酸血 急性肺损伤 机械通气 超氧化物岐化酶 丙二醛 

分 类 号：R563.8[医药卫生—呼吸系统]