The protective role of angiotensinIIreceptor inhibitor in ventilator-induced lung injury in rats

Objective To study the protective role of AngiotensinⅡreceptor inhibitor in ventilator-induced lung injury of rats.Method Forty healthy male SD rats were equally divided into four group (A,B,C,D group,n=10).Group A served as control group,group B had low tidal volume (V_T=10 ml/kg) with breathing rate (P)=80/min;group C had high tidal volume (V_T=40 ml/kg) group with breathing rate 80/min;group D had high tidal volume (V_T=40 ml/kg) group with breathing rate 80/min,all rats in group D were pretreated with Losartan.The duration of ventilation in 'all groups was two hours.Rats were sacrificed after experiment finished. The lung lavage liquid and lung tissue were collected and preserved with well established methods.Lung pathological change was observed by microscope;lung cell apoptosis was assessed with TUNEL;the expression of ANGⅡwas assayed with RT-PCR.The measured variables also included total protein,WBC,W/D,MPO. Results In comparison with B group,all variables in group C were significantly increased (P0.01).Whereas in comparison with group C,all variables measured in group D remarkably decreased (P0.05 or 0.01. Conclusions ANGⅡprobably plays an important role in VILI,and the specific blocking agent of ANGⅡreceptor (ATI) can remarkably alleviate ventilator-induced lung injury.