治疗性高碳酸血症减少大鼠肺移植后中性粒细胞弹性蛋白酶的分泌

Therapeutic hypercapnia attenuated the production of neutrophil elastase after lung transplantation in rats

目的 探讨治疗性高碳酸血症对大鼠左肺移植后中性粒细胞功能的影响.方法 雄性Wistar大鼠28只,按随机数字表法分为两组,每组中随机选择7只分为供体和受体实施左肺原拉移植.移植前受体均给予50%N2＋50%O2通气15 min,移植后,对照组给予50%O2通气;治疗组给予5%O2和一定浓度的CO2,维持动脉血二氧化碳分压在80 mm Hg～100 mmHg （1mm Hg=0.133kPa）,两组移植再灌注后观察90 min.记录平均动脉压变化并采集动脉血行血气分析,测量血清及肺泡灌洗液（bronchial alveolar lavage fluid,BALF）中的中性粒细胞弹性蛋白酶（neutrophil elastase,NE）及IL-8浓度,BALF中总蛋白含量,计算BALF中的中性粒细胞百分比.结果 治疗组的动脉血氧分压、血压明显高于对照组（P〈0.05）;治疗组血清中NE的含量明显低于对照组（13±4 vs 27±12）;移植后对照组血清中IL-8含量在移植后显著升高（1.08±0.17 vs 0.63±0.18,P〈0.01）,治疗组则变化不明显;治疗组BALF与对照组BALF相比,蛋白含量（2.78±0.25 vs 3.29±0.47）、IL-8浓度（0.97±0.08 vs 1.75±0.48）以及NE浓度（16±4 VS 26±9）均显著低于对照组;治疗组BALF中的中性粒细胞百分比显著低于对照组（27±12 vs 40±9,P〈0.05）.结论 高碳酸血症能够减少大鼠肺移植后NE的分泌,对肺移植后的缺血/再灌注损伤起到保护作用.

objective To investigate the effect of therapeutic hypercapnia on the function of neutrophil after the left lung transplantation in rats. Methods Male Wistar rats undergoing the left lung transplantation were divided into control group and therapy group（n= 14 in each group）, 7 for donator and 7 for receptor, randomly. Receptors were ventilated with 50% N2 ＋ 50% 02 before lung transplantation. Though it did not changed in the control group, the ventilated gases in the therapy group were mixed gases composed of N2,O2, and CO2 to keep PaCO2 within the range of 80～100 mmHg after lung transplantation. The observed period was 90 min after reperfusion of transplantation. The mean artery pressure（MAP） was recorded and arterial Blood Gas Analysis included PaO2, PaCO2 and pH was performed. The contents of Neutrophil Elastase（NE） and IL-8 in the plasma and in Bronchial alveolar lavage fluid （BALF） were measured. The level of protein in the BALF was evaluated, as well as the percentage of neutrophil. Results The MAP, PaO2 and PaCO2 were significantly higher in the therapy group than in the control group （P〈0.05）. The control group showed significantly higher plasma concentration of NE（27±12 vs 13±4） and percentage of neutrophil in the BALF（40±9 vs 27±12） compared with the therapy group（P〈0.05）. Animals in the control group had a significantly higher IL-8 plasma level than that of baseline after lung transplantation（1.08±0.17vs 0.63±0.18,P〈0.01）, but no significant difference was observed in the therapy group （0.8±0.3 vs 0.7±0.3）.3）. The levels of protein concentration （2.78±0.25 vs 3.29±0.47）, IL-8 （0.97±0.08 vs 1.75±0.48） and NE （16±4 vs 26±9） in the BALF were significantly lower in the therapy group than in the control group （P〈0.05）. Conclusion The therapeutic hypercapnia could attenuate the production of neutrophil elastase and provide protection against the ischemia-reperfasion injury after the lung transplantation.