Effects of Isoflurane Administration before Ischemia on Expression of Neutrophil Chemoattractant and the DNA Binding Activity of Nuclear Factor-κB in Lung Ischemia-Reperfusion Injury in Rats

Purpose To investigate the effects of isoflurane administration before ischemia on the gene expression of cytokine-induced neutrophil chemoattractant (CINC) and the DNA binding activity of nuclear factor-κB (NF-κB) in lung ischemia-reperfusion injury in rats. Methods The rat ischemia model with occlusion of left pulmonary hilum for 45 min was used in this experiment.One hundred and twenty male Sprague-Dawley rats were randomly divided into four groups.Group C (n=30):continuous perfusion wi-thout ischemia;group IR (n=30):interruption of perfusion and ventilation for 45 min,followed by reperfusion;group ISO-IR (n=30):one MAC isoflurane inhalation for 30 min before ischemia,followed by ischemia-reperfusion;group ISO-C (n=30):one minimal alveolar concentration(MAC) isoflurane inhalation for 30 min,followed by continuous perfusion.The changes of arterial blood gas analysis,the lung wet-to-dry weight ratio (W/D),myeloperoxidase (MPO) of lung,the expression of CINC mRNA and the DNA binding activity of NF-κB were studied at 45 min after pulmonary ischemia and 30,60,120 min of reperfusion.The cell counts,percentage of PMN and total protein (TP) content in left bronchoalveolar lavage fluid (BALF) was performed at 120 min of reperfusion.MAP was continuously monitored. Results During reperfusion,the lung W/D,MPO activity,expression of CINC mRNA and the DNA binding activity of NF-κB in IR and ISO-IR groups increased progressively and was evidently higher than that in C and ISO-C groups (P 0.05);but compared with IR group,preadministration of isoflurane could inhibit the increase of the indexes above-mentioned after 60 min of reperfusion (P0.05).The percentage of PMN in BALF of IR group was obviously increased compared with the other groups at 120 min of reperfusion (P0.05).IR significantly increased the content of TP in BALF of IR and ISO-IR groups,but the degree of increase in TP content of ISO-IR group was decreased markedly compared with IR group (P0.05).Histological examination showed that the degree of injury in ISO-IR group was significantly ameliorated compared with IR group. Conclusions Inhalation of isoflurane before ischemia could protect against ischemia-reperfusion induced lung injury in rat in vivo by inhibiting the sequestration of PMN in the lung possibly through inhibiting lung NF-κB activation and attenuating the expression of CINC mRNA during lung ischemia-reperfusion in rats.