比例辅助通气对重症胎粪吸入幼兔肺组织肿瘤坏死因子-α和白细胞介素-8水平的影响

Changes of tumor necrosis factor-αand interleukin-8 in severe meconium injured young rabbits treated by proportional assist ventilation

目的探讨比例辅助通气(PAV)对胎粪吸入幼兔肺组织中肿瘤坏死因子-α(TNF-α)和白细胞介素-8(IL-8)水平的影响。方法将30只日龄20～30天的幼兔随机分为灌入胎粪后实施PAV组和灌入胎粪后实施同步间歇指令通气(SIMV)组,并与胎粪吸入不予通气组(MAS组)及灌生理盐水组(对照组)进行比较,各组分别于8h后处死,ELISA法检测肺组织匀浆及肺泡灌洗液中TNF-α、IL-8的含量。结果 (1)肺组织湿干比PAV组(7.81±0.52)、SIMV组(8.79±0.96)、MAS组(7.12±0.74)均高于对照组(4.22±0.30),SIMV组高于PAV组和MAS组,差异有统计学意义(P均<0.05);PAV组与MAS组差异无统计学意义(P>0.05)。(2)PAV组、SIMV组和MAS组肺组织匀浆TNF-α含量(pg/ml)[(872.6±104.0)、(973.9±114.5)和(707.1±39.1)]及IL-8含量(pg/ml)[(787.0±89.3)、(872.9±87.0)和(641.4±60.3)]均高于对照组[(401.1±74.5)和(381.3±63.3)],SIMV组高于PAV组和MAS组,PAV组高于MAS组,差异有统计学意义(P均<0.05)。(3)PAV组、SIMV组及MAS组肺泡灌洗液TNF-a含量[(644.4±89.3)、(787.1±100.6)和(536.0±28.5)]均高于对照组(301.8±75.9),SIMV组高于PAV组,差异有统计学意义(P均<0.05);PAV组、SIMV组及MAS组IL-8含量[(653.0±93.3)、(744.7±81.8)和(532.4±60.1)]均高于对照组(280.9±70.8),SIMV组高于PAV组和MAS组,PAV组高于MAS组,差异有统计学意义(P均<0.05)。结论胎粪在炎症反应中可促进TNF-α、IL-8释放,PAV治疗MAS时所致肺损伤程度较SIMV小。

Objective To observe the changes of tumor necrosis factor-α （TNF-α） and interleukin-8 （IL-8） in severe meconium-injured young rabbits treated by proportional assist ventilation （PAV）. Methods Thirty 20 - 30 days rabbits were randomly assigned into four groups ： implementation of PAV after instillation of meconium （PAV group ）, implementation of synchronized intermittent mandatory ventilation after meconium instillation （SIMV group ）, and no ventilation after meconium instillation （ MAS group） and the saline irrigation with no ventilation group （ control group）. The animals in each group were sacrificed after 8 hours, lungs and trachea were excised. Levels of TNF-α, IL-8 in lung homogenate and bronchoalveolar lavage （BAL） fluid were measured by enzyme-link immunosorbent assay （ELISA）. Results （ 1 ） The lung wet/dry weight ratio of PAV group （7.81 ＋ 0.52）, SIMV group （8.79 ± 0. 96 ）and MAS group（7. 12 ± 0.74 ） were higher than that of control group （4. 22 ± 0. 30）, that of SIMV group was higher than that of PAV and MAS group, the difference were statistically significant （P 〈 0.05 ） ; There was no significant difference between PAV and MAS group. （2） The levels of both TNF-ot（pg/ml） [ （644. 4 ±89.3）vs. （787.1 ± 100. 6） vs. （536. 0 ±28.5） ] and IL-8 （pg/ml） [ （787.0 ±89.3） vs. （872.9 ±87.0） vs. （641.4 ±60. 3） ] in the lung homogenate of PAV group, SIMV group and MAS group were higher than that of control group [ （401.1 ±74. 5） vs. （381.3 ±63.3）]. that of SIMV group was higher than that of PAV and MAS group, the difference were statistieally significant （P 〈 0, 05 ） ; That of PAV group were higher than that of MAS group, the difference were signifieant （P 〈 0. 05 ）. （3） The levels of TNF-α in the BALF of PAV group （ 644.4 ± 89.3 ）, SIMV group （ 787. 1 ± 100. 6） and MAS group （536.0 ± 28.5 ） were higher than that of control group （ 301.8 ± 75.9 ）. That of SIMV group was higher than that of PAV group, the difference were significant （ P 〈 0. 05 ） ; The levels of IL-8 in the BALF of PAV group（653.0 ±93.3）, SIMV group （744.7±81.8）and MAS group（532.4 ± 60. 1 ） were higher than that of control group （280. 9 ± 70. 8 ）. that of SIMV group was higher than that of PAV and MAS group, that of PAV group were higher than that of MAS group, and the difference were significant （P 〈 0. 05 ）. Conclusions Meconium can promote TNF-α, IL-8＇s releasing during the inflammatory response ; In lung homogenates and BAL fluid, levels of TNF-α, IL-8 in PAV group are lower than that in SIMV group, suggesting that less lung injury in proportional assisted ventilation than SIMV.