多形核粒细胞渗透和早期NF-κB活性与深低温停循环肺损伤的评估

Polymorphonuclear Cells Infiltration and Early Activity of Nuclear Factor-kappa B in Empirical Study of Lung Injury in Deep Hypothermia and Circulatory Arrest

目的研究深低温停循环(deep hypothermia and circulatory arrest,DHCA)不同时段肺组织内核转录因子kappaB(nuclear factor-kappa B,NF-κB)、炎症因子和多形核粒细胞(polymorphonuclear cells,PMNs)的变化,推测PMNs渗透和早期NF-κB活性在DHCA肺损伤早期的作用,探讨其可能的机制,为肺保护策略提供实验依据。方法将12只幼猪随机分为两组,每组6只,常温平行循环组(对照组)和DHCA缺血-再灌注组(实验组),分别在不同时间点检测NF-κB和炎症因子的变化。结果两组在平行循环前肺组织标本中NF-κB均为阴性,胞核未见棕染,组间比较差异无统计学意义(P>0.05)。实验组在缺血-再灌注0.5h时肺组织细胞核内NF-κB的表达达到高峰,且棕染的细胞核以PMNs为主;而对照组平行循环后各时间点比较差异无统计学意义,肺组织标本仍为弱阳性。实验组肿瘤坏死因子-α(TNF-α)在缺血-再灌注1h时较再灌注前含量有显著性变化(P<0.05),白细胞介素-8(IL-8)、白细胞介素-6(IL-6)含量则在缺血-再灌注1.5h时较再灌注前有显著的变化(P<0.05);对照组平行循环后各时点与平行循环前比较差异有统计学意义(P<0.05),但平行循环后各时间点比较差异无统计学意义(P>0.05)。结论DHCA的早期激活NF-κB可能在DHCA肺损伤中起着重要的作用。

Objective To investigating the variance of nuclear factor-kappa B（NF-kB）,inflammatory factor and polymorphonuclear cells（PMNs） in lung, our study infer the role of PMNs infiltration and early activity of NF-kB in empirical study of lung injury in deep hypothermia and circulatory arrest. Our study also guess the possible mechanism of action in order to provide a more excellent program for lung protection. Methods Twelve immature pigs were randomly divided into two groups,there are six pigs in each group,one group was normothermic parallel circulation （control group）,the other was deep hypothermia and circulatory arrest （DHCA, experimental group）,we obtain lung tissue and venous blood from pigs to measure the variances of NF-kB by immunohistochemistry and inflammatory factor by enzyme-linked immunosorbent assay（ELISA） at different time. Results The expression of NF-kB of the lung tissue specimen was negative before parallel circulation in both groups, there was no brown dyed cell nucleus and the variation was no statistically difference in two groups. The expression of NF-kB reached it＇s peak at half an hour of ischemia reperfusion, and most of the brown dyed cell nucleus were PMNs, then the expression of NF-kB decreased in the experimental group. The lung tissue specimens were all weakly negative at the time points after parallel circulation and there was no statistical difference among them. But the content of inflammatory factor increased gradually from half an hour of ischemia reperfusion to two hour of ischemia reperfusion, which reached their peak at two hour of ischemia reperfusion. There was significance variances at the content of tumor necrosis factor-α（TNF-α） at one hour of ischemia reperfusion, while at one and a half hour of ischemia reperfusion. There was significance variance at the content of interleukin-8 and interleukin-6 in the experimental group. While in the control group, there was statistically difference before and after parallel circulation, but there was no statistically difference among the time points after parallel circulation. Conclusion The early activity of NF-kB may have an important role in lung injury of DHCA,treatments aim directly at NF-kB may provide an important strategy for lung injury of DHCA.