The protective effect of limited fluid resuscitation on hemorrhagic shock induced lung injury in mice

XIAO Hui; DING Ning

doi:10.3969/j.issn.1002-1949.2014.08.017

Abstract：Objective To investigate the protective effect of limited fluid resuscitation on hemorrhagic shock induced lung injury in mice .Methods Thirty-two healthy C57BL/6 mice were randomly divided into 4 groups (n =8 each): group A, control;group B, hemorrhagic shock; group C, hemorrhagic shock with limited fluid resuscitation and group D , hemorrhagic shock with traditional fluid resuscitation .The animals were resuscitation for 6 h and then all animals were sacrificed .Lung wet and dry weight ratio ( W/D ) was calculated , and lung pathologic changes were observed under light microscope .Total protein and WBC in bronchoalveolar lavage fluid ( BALF ) were determined .The expression of high mobility group box 1 ( HMGB1 ) and p -p38 protein and mRNA was measured by Western blot and RT-PCR, respectively.A p38 inhibitor SB203580 was used to investigate the effect on HMGB1 expression .Results Normal lung tissues were observed in group A .Significant pathological changes were observed in group B and D and milder changes were revealed in group C .Compared with group A, total protein and WBC in BALF , W/D lung weight ratio and MPO activity were significantly higher in group B ( P <0.05 ); HMGB1 protein and mRNA expression and p -p38 activity also significantly increased in group B (P<0.05).Compared with group B, the above indexes significantly decreased in group C (P<0.05), however, no significant changes were observed in group D (P>0.05 ) .Compared with control group , the expression of HMGB1 protein significantly decreased in SB203580 treatment group . Conclusion Limited fluid resuscitation attenuated hemorrhagic shock induced acute lung injury, and the underlying mechanism might be down -regulation of HMGB1 through p38 MAPK signal pathway .