海水淹溺肺水肿大鼠肺血管通透性变化的观察

Changes of pulmonary capillary permeability in rats with pulmonary edema caused by seawater drowning

目的研究海水淹溺肺水肿大鼠的肺血管通透性变化与超氧化物歧化酶(SOD)、丙二醛 (MDA),髓过氧化物酶(MPO)的关系。方法 16只雄性SD大鼠按随机表法随机分为对照组和淹溺组,均以伊文思蓝(EB)20 mg／kg静脉注射,淹溺组气管内注射海水4 ml／kg,建立海水淹溺性肺水肿大鼠模型,于注射4 h后处死大鼠,计算肺组织湿重／干重比(W／D),取肺组织做病理切片HE染色,高倍镜下中性粒细胞(PMN)计数,测定肺组织中的EB浸出量(每100 mg湿肺用1 ml甲酰胺浸泡),测定肺组织匀浆中的SOD、MDA、MPO含量,以及血浆的SOD、MDA含量。结果对照组和淹溺组结果分别为: W／D 4．45 ±0．18、8．61±0．42,P<0．05;PMN(13．6±3．4)、(120．2±21．2)个／高倍视野,P<0．05;肺组织EB浸出量(18．4 ±1．8)、(30．9±4．1)μg/ml,P<0．05;肺匀浆MPO(0．64±0．08)、(1．14 ±0．16)活力单位／g湿片,P<0．05;SOD(75．6±11．7)、(67．6±10．3)U／mg protein,P>0．05;MDA(1．32±0．21)、 2．21±0．33 nmol／mg protein,P<0．05;血浆中的SOD(96．6±29．3)、(92．3±33．9)U／mg protein,P> 0．05;MDA(8．24±1．79)、(15．21±2．93)nmol／ml,P<0．05。结论海水淹溺后4 h肺血管通透性明显增加,组织湿重／干重比、中性粒细胞计数、MPO含量、血浆和肺组织匀浆中的MDA含量均增加。血浆和肺组织匀浆中的SOD未见明显变化。

Objective To study changes of pulmonary capillary permeability in rats with pulmonary edema caused by seawater drowning （PE-SWD） and the relationship between superoxide dismutase （SOD）, maleic dialdehyde （MDA）, and myeloperoxidase （MPO）. Methods Sixteen male Sprague-Dawley rats were randomized into 2 groups： drowning group and control group. Both groups were injected with 20mg/kg Evan＇ s blue intravenously. Rat animal model of PE-SWD was obtained by injecting 4 ml/kg seawater intratracheally. The rats were sacrificed 4 h after injection and lungs were removed for pathological examination under microscopes. The infiltrated polymorphonuclear leukocyte （PMN） and the lung tissue wet/dry weight （W/D） ratio were calculated. Lung Evan＇ s blue content was extracted with formamide （ lml formamide/100 g wet lung） and was determined. MPO, SOD, and MDA contents in lung parenchyma, and SOD and MDA contents in plasma were detected. Results W/D, PMN, and Evan＇ s blue contents in the control group and the seawater drowning group were 4.45 ± 0.18 vs 8.61 ± 0.42, 13.6 ± 3.4 vsl20.2 ± 21.2/high power field, and 18.4 ± 1.8 vs 30.9 ± 4. 1μg/ml, respectively. MPO, SOD, and MDA in lung parenchyma were 0.64 ± 0.08 vs 1.14 ± 0. 16 U/g wet lung,75.6 ± 11.7 vs 67.6 ± 10. 3 U/mg protein, 1.32 ± 0.21,2.21 ± 0.33 nmol/mg protein,respectively（ P 〈0.05 ,above all）. SOD and MDA in plasma were 96.6 ± 29.3 vs 92.3 ± 33.9 U/mg protein ,and 8.24 ± 1.79 vs 15.21 ± 2.93 nmol/ml （ P 〈 0.05 ）. Conclusions The pulmonary capillary permeability in rats with pulmonary edema of PE-SWD was significantly increased, and so were W/D, PMN, MPO in lung parenchyma,and MDA in both lung parenchyma and plasma. But no significant change of SOD in lung parenchyma and in plasma was observed.