Expression Changes And Significance Of AQP-1 And AQP-5 In Rats With Acute Lung Injury During The Early Stage Induced By Paraquat

ObjectiveThe model of acute lung injury induced by paraquat in rats was studied in this study, to observe the expression changes of AQP1 and AQP5 in the rats' lung tissues with the early stage of ALI induced by paraquat(PQ) and discuss their significance in ALI/ARDS.Methods48 clean SD healthy male rats were randomly assigned into two groups:PQ gavage group(n=24)which were gavaged 1ml prepared PQ solution one time, normal saline(NS) control group(n=24)which were gaveged 1ml normal saline and the other treatments were as the same as the PQ gavage group.All the rats were observed and anaesthetized at 3h,6h,12 h,24h after treatment. Taking Aorta abdominalis blood to determine blood gas analysis, using light microscopy to observe pathological changes in pulmonary tissue, using BCA(bicinchonininc acid) method to determine the concentration of bronchoalveolar lavage fluid, taking part of lungs,weighing it and calculating the W/D, using enzyme linked immunosorbent assay(ELISA) to determine interleukin-6(IL-6) and tumor necrosis factor-alpha(TNF-?) levels in serum, real-time fluorescent quantitative PCR and western-blot were used to detect aquaporin1 and aquaporin5 expression at the m RNA and the protein level respectively.Result1.The histopathological changes in lungsMicroscopic view:The microscopic view of NS gavage group rats' lung tissue is that the alveolar's structure is complete, the wall thin, and had no hyperaemia edema in alveolar and lung interstitium. While the microscopic view is that the alveolar edema, it's structure destroyed, and some had different degrees of collapse, and the lung interval was enlarged, inflammatory cells infiltration, red blood cells lysis, and hyaline membrane formation in rats' lung tissue in PQ gavage group.2.Changes of arterial blood gas analysisThe Pa O2, Pa CO2 and Pa O2/Fi O2 of PQ gavage group decreased significantly, while the NS group were normal. The Pa O2, Pa CO2, Pa O2/Fi O2 of PQ gavage group were obviously lower than that of NS gavage group at 3h,6h,12 h,24h(p<0.05).3.Changes of lung W/DThe lung W/D increased and kept increasing during the experiment in PQ gavage group, and was obviously higher than that in NS gavage group(p<0.05).4.Changes of IL-6, TNF-? levels in serumThe levels of IL-6 and TNF-a in serum in PQ gavage group increased quickly and reached the highest point at 12 h, then they were always at a high level, and significantly higher than that of NS gavage group(p<0.05).5.Changes of the concentration of protein in BALFCompared with NS control group,The total protein in BALF in PQ gavage groupis higher(p<0.05)6.Changes about expression of AQP1The expression of AQP1 at m RNA and protein level in PQ gavage group was significantly lower than that in normal saline gavage group(p<0.05).7.Changes about expression of AQP5The expression of AQP5 at m RNA and protein level in PQ gavage group was significantly lower than that in normal saline gavage group(p<0.05).8.Correlation and linear regression analysis about the expression of AQP1,AQP5 and concentration of IL-6,TNF-? in serum.After PQ gavage, the expression of AQP1,AQP5 m RNA and protein level in lung tissues showed a significant negative correlation with the concentration of IL-6, TNF-? in serum(p<0.01), and the effect of concentration of IL-6, TNF-? in serum to the expression of AQP1,AQP5 is significantly.Conclusion1.The changes of expression of AQP1 and AQP5 have affected the regulation of lung water balance in acute lung injury induced by paraquat.