不同程度呼吸机相关性肺损伤大鼠血清CC10蛋白水平的比较

目的 比较不同程度呼吸机相关性肺损伤(VILI)大鼠血清CCIO蛋白的水平.方法 清洁级Wistar大鼠40只,雌雄不拘,体重200～250 g,随机分为5组(n=8),对照组(Ⅰ组)仅切开气管,不行机械通气;轻度肺损伤组(Ⅱ组)潮气量(VT)7 ml/kg,机械通气2 h;中度肺损伤组(Ⅲ组)VT 7 ml/kg,机械通气4 h;重度肺损伤组(Ⅳ组)VT 40 ml/kg,机械通气2 h;极重度肺损伤组(Ⅴ组)VT 40 ml/kg,机械通气4 h.Ⅰ组在气管切开后即刻,其余各组在机械通气结束时采集腹主动脉血3 ml,并收集支气管肺泡灌洗液(BALF),测定血清和BALF中CC10蛋白水平;观察肺Clara细胞;计算肺湿/干重比(W/D).结果 Ⅳ组和Ⅴ组终末细支气管、呼吸细支气管管腔有大量脱落Clara细胞,血管壁有大量漏出的CC10蛋白,其余组上述表现不明显;Ⅱ组～Ⅴ组血清CC10蛋白水平逐渐升高,肺组织损伤程度逐渐加重(P＜0.05);与Ⅰ组、Ⅱ组和Ⅲ组比较,Ⅳ组和Ⅴ组BALF中CC10蛋白水平降低(P＜0.05);血清CC10蛋白水平与肺组织损伤程度和肺W/D呈正相关,相关系数分别为0.915和0.846(P＜0.01);BALF中CC10蛋白水平与肺组织损伤程度和肺W/D呈负相关,相关系数分别为-0.799和-0.816(P＜0.01).结论 血清CC10蛋白水平与大鼠呼吸机相关性肺损伤程度有关.

The relationship between serum CC10 protein and ventilator-associated lung injury in rats

Objective To investigate the relationship between serum CC10 protein and lung injury induced by mechanical ventilation.Methods Forty healthy Wistar rats of both sexes weighing 200-250 g were randomly divided into 5 groups(n=8 each):group Ⅰ control;group Ⅱ mild lung injuryVT=7 ml/kg,duration of mechanical ventilation(t):2 h];group Ⅲ moderate lung injury(VT=7 ml/kg,t=4 h);group Ⅳ severe lung injury(VT=40 ml/kg,t=2 h);group Ⅴ extremely severe lung injury(VT=40 ml/kg,t=4 h).The animals were anesthetized with intraperitoneal 10% chloral hyrdrate 3.5 ml/kg and tracheostomized.Group Ⅰ received no mechanical ventilation.The animals in group Ⅱ-Ⅴ were mechanically ventilated with air(FiO2=21%,RR=40 bpm,I:E=1:2).The animals were sacrificed at the end of mechanical ventilation.The lungs were immediately removed for microscopic examination and determination of W/D lung weight ratio.The left lung was lavaged.The CC10 protein level in broncho-alveolar lavage fluid(BALF)and serum were determined by Western blotting.The Clara cells in the bronchiolar epithelium were examined by immno-histochemistry.Results The level of CC10 protein in BALF was significantly lower in group Ⅳ and Ⅴ while the serum CC10 protein level was significantly higher in group Ⅱ-Ⅴ than in group Ⅰ.The serum CC10 protein level was positively correlated while the CC10 protein level in BALF was negatively correlated with the severity of lung injury and W/D ratio.Conclusion The serum CC10 protein is closely related to the severity of lung injury induced by mechanical ventilation.