The roles of cytokines and water sodium channel proteins in acute kidney injury-induced acute lung injury rats
10.3760/cma.j.issn.1671-0282.2013.03.004
- VernacularTitle:细胞因子和水钠通道蛋白在急性肾损伤致肺损伤中的作用
- Author:
Tao MA
;
Zhi LIU
- Publication Type:Journal Article
- Keywords:
Acute kidney injury;
Acute lung injury;
Cytokine;
Aquaporin 1;
Epithelial sodium channel protein
- From:
Chinese Journal of Emergency Medicine
2013;22(3):242-247
- CountryChina
- Language:Chinese
-
Abstract:
Objective To observe the physiopathologic changes of lung in rats with acute ischemic kidney injury,and to study the roles of cytokine,epithelial sodium channel protein (ENaC) and aquaporin 1 (AQP1) in acute lung injury brought on by acute ischemic kidney injury in rats.Methods A total of 60 healthy male Wistar rats (300-320 g) were randomly (random number) divided into control groups (group A,n =30) and acute kidney injury group (group B,n =30).The model of acute ischemic kidney injury in rats was made by bilateral renal arteiovenous blockage with clamps.Six rats of each group were sacrificed at 0,2,4,6 and 8 hours after modeling.Lung tissue of rats was harvested and stained with hematoxylin-eosin (HE) staining method,and the pathological changes of lung were observed under microscope.The ratio of wet and dry weight (W/D) of lung was calculated.The levels of protein in bronchoalveolar lavage fluid (BALF) were measured.The levels of IL-6 and TNF-α both in serum and BALF were tested.The concentrations of AQP1 and α-ENaC in lung were measured.Results At six hours after modeling,the pH value of arterial blood of rats in group B began to get lowered compared to group A.There was no difference in partial pressure of oxygen in arterial blood between two groups during entire period of experiment (P >0.05).Protein level in BALF and W/D of lung increased significantly two hours after modeling in rats of group B (P < 0.05).The histopathological changes of acute lung injury including swollen aleolar epithelium,widened interalveolar septum,edema of alveoli and alveolar interstitium,alveolar neurophil sequestration,erythrocytes and protein in exudates were observed.The levels of TNF-α and IL-6 in serum and in BALF began to increase at two hours after modeling.The levels of AQP1 and α-ENaC of lung in rats with acute kidney injury decreased gradually and were lower than those in rats of group A (P <0.05).Conclusions Aleolar epithelial-endothelial barrier function was already compromised at the beginning of AKI,suggesting the acute lung injury was already brought on.The levels of TNF-α,IL-6 in serum and in BALF increased after the occurrence of acute kidney injury.The decreases in lung AQP1 and α-ENaC might contribute to the lung injury caused by early acute kidney injury.