Alveolar cells apoptosis and Fas/FasL expression in rabbits after ischemia/reperfusion of pulmonary artery / 第二军医大学学报

ABSTRACT

Objective: To observe the changes of alveolar cells apoptosis and the expression of Fas/FasL protein in pulmonary injury induced by ischemia/ reperfusion in rabbbits, and to explore the related mechanism of pulmonary injury. Methods: The left pulmonary arteries of 30 healthy New Zealand rabbits (either sex) were obstructed and reperfused by inflating and discharging gas of 5F Berman sacculus catheter. The rabbits were then randomly divided into 5 groups sham operation group, ischemia 1 h group, ischemia 2 h group,ischemia 2 h and reperfusion 1 h group,and ischemia 2 h and reperfusion 2 h group. Another 6 healthy rabbits were taken as control. The pulmonary tissues were harvested after experiment and the lung wet/dry ratio was determined. Alveolar cells apoptosis and Fas/FasL protein expression were determined using flow cytometry and immunocytochemistry techniques,respectively. Results: The lung cell apoptosis was obviously increased in ischemia groups compared with that in the control and sham group. The reperfusion after ischemia further increased the cell apoptosis compared with simple ischemia groups, and the apoptosis was positively related with the reperfusion time (P<0.05 or 0.01). Fas and FasL protein expression was significantly higher in ischemia and ischemia/reperfusion group than that in other groups (both P<0.01). Significant positive correlation was found between apoptosis index with lung wet/dry ratio and expression of Fas and FasL (r=0.769, 0.820,0.820 respectively, P<0.01). Conclusion: Pulmonary artery ischemia/reperfusion may activate the Fas/FasL system and induce alveolar cells apoptosis, leading to pulmonary damages.