title: New insights of aquaporin 5 in the pathogenesis of high altitude pulmonary edema.
abstract: BACKGROUND
  High altitude pulmonary edema (HAPE) affects individuals and is characterized by alveolar flooding with protein-rich edema as a consequence of blood-gas barrier disruption. In this study, we hypothesized that aquaporin 5 (AQP5) which is one kind of water channels may play a role in preservation of alveolar epithelial barrier integrity in high altitude pulmonary edema (HAPE).
  
  
  METHODS
  Therefore, we established a model in Wildtype mice and AQP5 -/- mice were assingned to normoxic rest (NR), hypoxic rest (HR) and hypoxic exercise (HE) group. Mice were produced by training to walk at treadmill for exercising and chamber pressure was reduced to simulate climbing an altitude of 5000 m for 48 hours. Studies using BAL in HAPE mice to demonstrated that edema is caused leakage of albumin proteins and red cells across the alveolarcapillary barrier in the absence of any evidence of inflammation.
  
  
  RESULTS
  In this study, the Lung wet/dry weight ratio and broncholalveolar lavage protein concentrations were slightly increased in HE AQP5 -/- mice compared to wildtype mice. And histologic evidence of hemorrhagic pulmonary edema was distinctly shown in HE group. The lung Evan's blue permeability of HE group was showed slightly increased compare to the wildtype groups, and HR group was showed a medium situation from normal to HAPE development compared with NR and HE group.
  
  
  CONCLUSIONS
  Deletion of AQP5 slightly increased lung edema and lung injury compared to wildtype mice during HAPE development, which suggested that the AQP5 plays an important role in HAPE formation induced by high altitude simulation.
authors.forename: Jun
authors.initials: J
authors.lastname: She
authors.forename: Jing
authors.initials: J
authors.lastname: Bi
authors.forename: Lin
authors.initials: L
authors.lastname: Tong
authors.forename: Yuanlin
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Pulmonary Medicine, Zhongshan Hospital, Fudan University, NO,180 Fenglin Road, Shanghai 200032, China. bai.chunxue@zs-hospital.sh.cn.
authors.forename: Chunxue
authors.initials: C
authors.lastname: Bai
mesh_terms: D000418:Albumins / Q000378:metabolism; D000531:Altitude; D000532:Altitude Sickness / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D051402:Aquaporin 5 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D015824:Blood-Air Barrier / Q000378:metabolism* / Q000473:pathology; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D002199:Capillary Permeability; D004195:Disease Models, Animal; D006976:Hypertension, Pulmonary / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000860:Hypoxia / Q000150:complications; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D005082:Physical Exertion; D011650:Pulmonary Alveoli / Q000378:metabolism* / Q000473:pathology; D013997:Time Factors
chemical_list: D000418:Albumins; C496038:Aqp5 protein, mouse; D051402:Aquaporin 5