The effects of propofol on the ventilator-induced lung injury and aquaporins 5 expression in rats

Objective To investigate the effects of propofol on ventilator- induced lung injury and the expression of aquaporin 5(AQP-5) in rats. Methods Fifty male Wistar rats were randomly divided into 5 groups: standard ventilation group(Group A,VT=8 mL/kg); high- tidal volume ventilation group(Group B,VT=30 mL/kg); propofol treated groups(Group C,D,and E,in which propofol 5 mg/kg 1h before,immediately after and 1h after high- tidal volume ventilation(30 mL/kg) was given,respectively,followed with infusion of propofol at 10 mg/(kg·h) until 4h after ventilation). Lung tissues were collected for calculation of wet / dry lung weight ratio( W / D),lung permeability index(LPI),and lung pathologic change. The expressions of AQP-5 mRNA and protein were also assessed. Results When compared with Group A,significant increase in W / D and LPI,with down- regulation in AQP-5 mRNA and protein were observed in the other 4 groups(P0. 05). When compared with Group B,significantly lower W / D and LPI,with up-regulation in AQP-5 were observed in Group C and D(P0. 05). Morphological changes and neutrophil sequestration were also less in Group C and D. Conclusion Early propofol administration provides protective effects on the lung injury induced by ventilator,which may be related to the up- regulation of AQP-5.