不同潮气量机械通气大白兔肺组织TNF-α和CC16的变化

Effects of Mechanical Ventilation at Different Tidal Volumes on the Expression of TNF-α and CC16 in the Lung of Rabbits

目的探讨不同潮气量(TV)机械通气对大白兔肺组织TNF-α和CC16的影响。方法将30只健康雄性大白兔按随机数字表随机分成对照组、小潮气量组及大潮气量组,每组10只。对照组插管后不进行机械通气,其他组插管后机械通气,小潮气量组TV 8 ml/kg,大潮气量组TV 25 ml/kg,其他参数相同。通气时间24 h。观察实验前后动脉血氧分压变化、ELISA法测定肺组织TNF-α及CC16、测定肺组织湿/干重(W/D)值、制备肺组织石蜡切片,在显微镜下观察肺组织病理学变化。结果与对照组比较,大潮气量组实验结束动脉氧分压降低(P<0.05),肺组织W/D、TNF-α升高,CC16降低(P<0.01),小潮气量组相应指标无显著变化(P>0.05)。大潮气量组肺组织病理切片可见肺组织水肿。结论大潮气量机械通气发生了呼吸机相关性肺损伤(VILI),表现为动脉氧分压、肺组织W/D、TNF-α、肺组织病理切片的变化,而同时肺组织CC16下降,表明CC16可能在VILI发病机制中起重要作用。

Objective To explore the effects of mechanical ventilation at different tidal volumes on the ex- pression of TNF-α and Clara cell secretory 16-kD protein （CC16） in the lung of rabbits. Methods Thirty healthy male rabbits were randomly divided into three groups, control group, low tidal volume group （L-TV group） and high tidal volume group （H-TV group）, 10 rabbits in each group. Mechanical ventilation was performed in all the groups after intubation except for control group, tidal volume was 8ml/kg in the L-TV group while 25ml/kg in the H-TV group, and other parameters in the three groups were the same. Mechanical ventilation lasted for 24 hours. Changes of arterial partial pressure of oxygen before and after experiment were observed. The levels of TNF-α and（CC16） in the lung tissues were detected by ELISA, and the wet-to-dry weight（W/D） ratio of lung tissues was calculated. Lung tis- sue sections were prepared for biopsies, and the histopathologic changes in the lung tissues were observed with micro- scope. Results The arterial partial pressure of oxygen decreased in the H-TV group compared with control group （P 〈0.05 ） ,the W/D ratio and TNF-ot level increased in the lung tissues while CC16 level decreased（ P 〈 0.01 ）, the corresponding indices showed no significant changes in the L-TV group（P 〉0.05） . Lung tissue edema could be ob- served in the H-TV group with lung tissue biopsy. Conclusion High tidal volume mechanical ventilation produces ventilator-induced lung injury（VILI） ,which present the change of arterial partial pressure of oxygen,lung tissue W/ D,TNF-α,and biopsy of lung pathology. CC16 in the lung tissues decreases at the same time, which indicates that CC16 may play an important role in the occurrence and development of VILI.