title: [Permeability of the air-blood barrier to macromolecules].
abstract: Serum macromolecules such as albumin or type G immunoglobulins are found in the film lining the alveolus, by virtue of techniques of broncho-alveolar lavage as well as demonstration by immunocytochemistry. Passage of such molecules may be studied experimentally by the use of tracers. Two barriers are found: a first at the level of the vascular endothelium which is relatively permeable and a second which is relatively impermeable at the site of the alveolar epithelium. Rupture of this barrier during non-hemodynamic oedema is responsible for massive passage of serum proteins to the alveolus, in particular of fibrinogen.
mesh_terms: D001980:Bronchi / Q000378:metabolism; D004727:Endothelium / Q000378:metabolism; D006801:Humans; D008168:Lung / Q000098:blood supply / Q000378:metabolism*; D010539:Permeability; D011506:Proteins / Q000378:metabolism; D011650:Pulmonary Alveoli / Q000378:metabolism; D011654:Pulmonary Edema / Q000378:metabolism
chemical_list: D011506:Proteins
vernacular_title: Perméabilité de la barrière air-sang aux macromolécules.