Abstract: AIM :To observe the expression change of ADAR1 gene of alveolar macrophages( AM_s) in acute lung injury( ALI) and what role ADAR1 gene maybe play in the disease .METHODS:The ALI model was induced by intratracheal administration of LPS and bronchoalveolar lavage fluid cells were counted by hemacytometer .For the differential cell count, the cells in BALF, which centri- fuged to glass slides using cytospin cartridge were stained with a modified Wright/Giemsa stain and the percent of AM_s was got ;at the same time, RT-PCR was carried out to measure the expression change of adar1 gene in the ALI models .RESULTS:The total cell count in BAL, which collected from successfully induced ALI models by intra- tracheal administration of LPS at the dose of 2 .5 mg·kg ^-1 increased sharply , from 1 .74 ×10⁶ in control group to the peak 17 .13 ×10⁶ , 1 .70 ×10⁶ at 6 h and 9 h respectively as ALI developed after IT LPS ;The absolute count of AM_s increased especially at 6 h to 9 h after IT LPS, while the percent of AM_s decreased from nearly 98 %in sham group to 21 % in ALI model group .The expression of ADAR1 gene increased time-dependently, especially at 6 h and 9 h of ALI.CONCLUSION:The absolute count of AM_s increases significantly in ALI model and ADAR1 gene of AM_s expression also increases .ADAR1 gene of AMs may play a very important role in ALI .

Key words: acute lung injury , alveolar macrophag- es , lipopolysaccharides , bronchoalveolar lavage fluid , ADAR1 gene