高原再灌注性急性肺损伤中多核粒细胞的作用

Role of Polymorphonuclear Leukocytes in Acute Lung Injury following Reperfusion at Highaltitude

目的：探讨多核粒细胞在高原家兔后肢缺血再灌注后造成急性肺损伤发生过程中的作用．方法：４０只家兔随机分为Ⅰ组（正常对照组）、Ⅱ组（单纯缺血组）、Ⅲ组（再灌注３０分钟组）、Ⅳ组（再灌注６０分钟组）、Ⅴ组（再灌注１２０分钟组）．在海拔３７００ｍ高原缺氧地区进行实验，采用家兔后肢缺血再灌注后造成急性肺损伤的动物模型，观察肺组织丙二醛（ＭＤＡ）、外周血白细胞（ＷＢＣ）计数、ＷＢＣ粘附率、肺泡间隔多核粒细胞（ＰＭＮ）计数、组织学及超微结构等指标，实验动物双后肢缺血４小时后恢复肢体血流．结果：Ⅱ组除支气管肺泡灌洗液（ＢＡＬＦ）中，ＷＢＣ计数明显增多外，各项指标无显著变化．Ⅲ、Ⅳ、Ⅴ组肺组织ＭＤＡ含量明显增高（Ｐ＜０．０１）；外周血及ＢＡＬＦ中ＷＢＣ计数、ＷＢＣ粘附率及肺泡隔ＰＭＮ计数等指标均有显著变化（Ｐ＜０．０５或Ｐ＜０．０１）．组织学及超微结构发现Ⅲ、Ⅳ、Ⅴ组肺微血管内有大量的ＰＭＮ聚集．结论：急性肺损伤的发生与ＰＭＮ有密切关系．

Aim: To study the effect of polymorphonuclear leukocytes (PMN) in acute lung injury following reperfusion at highaltitude.Methods: The experimental animals were subjected to four hours of hind limbs ischemia, then reperfused. The lung tissue malondialdehyde (MDA), the counts of white blood cells (WBC) in peripheral blood, the adhesive rate of WBC, and PMN in the lungs were observed. The lungs were also observed histologically and ultrastructurally. Results: A significantly increase of lung MDA and an obvious decrease of WBC counts were noted in 30, 60 and 120 minutes after reperfusion compared with controls. In addition, the values of WBC counts in bronchoalveolar laveage fluid (BALF), the adhesive rate of WBC and the quantitative counts of PMN in the lungs were significantly different from those in the control group. There were many PMNs around the micrangium of the lungs histolgically and ultrastructrally. Conclusion: It suggests that PMNs and oxygenfree radicals play a key role in the acute lung injury after lower torso ischemia / reperfusion.