Comparative aspects of salt and water transport across lung.
Calculation suggests that the outward flux of water from the surface of the lung into the expired air could be driven by a relatively small standing osmotic gradient. The structure of this alveolar epithelium does not appear to possess the characteristics of a typical secretory epithelium. These considerations argue against the occurrence of active transport in the alveoli of the adult mammalian lung.
D000818:Animals; D001693:Biological Transport, Active; D001834:Body Water / Q000378:metabolism*; D002199:Capillary Permeability; D006801:Humans; D008168:Lung / Q000378:metabolism*; D009995:Osmosis; D011650:Pulmonary Alveoli / Q000098:blood supply / Q000378:metabolism; D012119:Respiration; D012964:Sodium / Q000378:metabolism*
D012964:Sodium