Effect of hyperbaric oxygen preconditioning on the expression of lung aquaporin-1 in the rat model of high altitude pulmonary edema

Objective To investigate the effect of hyperbaric oxygen preconditioning on the expression of lung aquaporin-1 in the rat models of high altitude pulmonary edema. Methods Thirty-eight Wistar rats were randomly divided into 3 groups： the control group （the C group ）,the HBO group and the high-altitude pulmonary edema group （the HAPE group）. Western blot and real-time PCR were applied to determine the expression of AQP-1 in the lung of animals in each group. The wet-to-dry weight ratio （ W/D weight ratio） and morphology of the lung were also examined. Results Experiments showed that the W/D weight ratio of the HAPE group was obviously higher than that of the C group,lung injury scores of the HBO group were much lower than those of the HAPE group,AQP-1 and AQP-1 mRNA for the HAPE group decreased markedly at the protein and gene level than those of the C group,and that AQP-1 and AQP-1 mRNA for the HBO group were significantly higher than those of the HAPE group. Conclusions Decreased expression of AQP-1 might be involved in the mechanism of HAPE incidence. HBO preconditioning could positively regulate the expression of AQP-1 and at the same time prevent and alleviate effects of HAPE. Our study might be the first one introducing HBO preconditioning in the prevention of HAPE,and the first investigation on the expression of AQP-1 in a rat model of HAPE. Key words: Aquaporin-1 ;  Hyperbaric oxygen preconditioning;  High altitude pulmonary edema; Lung morphology Lung wet-to-dry weight ratio;