TNF-α在肺栓塞犬再灌注损伤中的作用及吸入NO对其影响

Role of TNF-α to reperfusion injury in canine model of PTE and effects of inhaled NO

目的建立血栓栓塞1周的犬肺栓塞(PTE)模型,观察该模型缺血-再灌注后不同时间点血清肿瘤坏死因子-α(TNF-α)的变化、肺泡腔内中性粒细胞(PMN)计数及吸入20ppmNO对其影响。方法对上述PTE犬行取栓术,酶联免疫吸附试验(ELISA)法检测对照组、缺血组、再灌注前、再灌注后2、4、6h及吸入NO组血清TNF-α含量(pg/ml,下同)的变化及各组术后6h肺泡腔PMN数量变化。结果再灌注组再灌注6h后血清TNF-α含量高于再灌注前及再灌注2h(8.90±1.43vs5.67±1.43,6.54±1.53,P<0.05);吸入NO组较再灌注组TNF-α含量有减少趋势(7.28±1.49vs8.90±1.43,P>0.05);再灌注6h后,再灌注组血清TNF-α浓度高于sham组及缺血组(8.90±1.43vs5.44±1.58,6.28±0.94,P<0.05);再灌注组肺泡腔PMN数(单位:/10HPF,下同)高于缺血组及Sham组(31±11vs8±4,1±1,P<0.05);吸入NO组肺泡腔PMN数低于再灌注组(19±6vs31±11,P<0.05)。结论血清TNF-α及PMN参与了该PTE犬模型的再灌注肺损伤;吸入20ppmNO可通过降低血清TNF-α含量及减少PMN向肺泡腔的渗出而减轻再灌注损伤的炎症反应。

Objective Aim To investigate the serum concentrations of tumor necrosis factor-α （TNF-α, pg/ml） at different time after reperfusion in the pulmonary embolism（PE） canine model embohzed for one week and the effects of inhaled 20 ppm NO to the TNF-α concentration and the alveolar polymorphonuclear leucocyte （PMN,/10HPF）. Methods Serum concentrations of TNF-α were measured by ELISA at 2,4,6 hours after reperfusion in the four groups ： sham, ischemia, reperfusion group and reperfusion group with inhaled 20 ppm NO. The quantities of the alveolar PMN were measured when the canines were sacrificed at 6 hours after operation in the different groups. Results The serum TNF-α concentration in the reperfusion group at 6 hours after reperfusion were significantly higher than before reperfusion and 2 hours after reperfusion（8.90 ± 1.43 vs 5.67 ± 1.43,6. 54 ± 1.53 ,P 〈0. 05 ） ; And the TNF-α concentrations showed a decreasing tendency in the reperfusion group with inhaled NO than in the reperfusion group（7.28 ± 1.49 vs 8. 90 ± 1.43,P 〉0. 05）. At 6 hours after reperfusion, the TNF-α concentration in the reperfusion group were significantly higher than the sham and ischemia groups（ 8.90 ± 1.43 vs 5.44 ± 1.58,6.28 ± 0.94, P 〈 0.05 ）. The quantities of the alveolar PMN in the reperfusion group were significantly higher than sham and ischemia group （ 31 ± 11 vs 8 ± 4, 1 ± 1, P 〈 0. 05） ;while they were significantly decreased in the reperfusion group with inhaled NO than the reperfusion group（ 19 ± 6 vs 31 ± 11, P 〈 0. 05 ）. Conclusion The serum TNF-α and alveolar PMN are involved in the reperfusion injury of the PTE canine model. Reperfusion injury in the model may be ameliorated by inhaling 20 ppm NO which may reduced the serum TNF-α concentrations and inhibit the circulating PMN infiltrating the alveolar.