Study of AQP-5,NF-κB,TNF-α content and mRNA express in rats lung after deep hypothermic circulatory arrest

Objective To discuss the changes and significance of Aquaporin 5( AQP 5),NF-κB and TNF-α mRNA in acute lung injury in rats.Methods Forty wistar rats were randomized into experimental group,control group and normal group.The rats of experimental group were blocked left lower hilus pulmonis after it' s body temperature cooled to deep hypothermia.The rats of control group were only thoracotomy and not blocked left lower hilus pulmonis.The lung specimens were pathology observated and measuremented wet / dry weight ratio,which were taken by before blocked,blocked 30 min,60 min,2 h,and reperfused 12 h,24 h.There were TNF-α,NF-κB,AQP-5, which transcription was detected by real-time PCR method.Results The experimental group lung tissue AQP-5 content and mRNA express peaked( P 0.01) after blocked 30 min and decreased to 24 h after reperfusion,W / D ratio and inflammatory mediators transcription express beginning to rise after blocked 30 min( P 0.01),peak appeared in the reperfusing 12 h.The control group lung tissue AQP5 content and mRNA express peaked( P 0.01) after deep hypothermia 30 min and decreased to 24 h after rewarming,W / D ratio and TNF-α,NF-κB transcription express beginning to rise after deep hypotherima 60 min( P 0.05),peak appeared in the rewarming 12 h.The change of indication between experimental group with control group was more obvious( P 0.05).Conclusion Deep hypotherima have protective effect to the lungs in the short term,but with the extension of time, the content and mRNA express of NF-κB and TNF-α were constantly rising,the content and mRNA express of AQP5 was constantly descending,which caused acute lung injury,and based on this,ischemia-reperfusion injury make further aggravating.