Alterations of mechanical properties and morphology in excised rabbit lungs rinsed with a detergent.
To assess the influence of alterations of lung surfactant on the geometry of peripheral air spaces, the morphology of detergent-rinsed rabbit lungs was studied. In comparison to normal excised rabbit lungs, fixed in the same manner by vascular perfusion at different points on the deflation pressure-volume curve, the most important differences are as follows. 1) With decreasing lung volume there is a progressive collapse of alveoli; at low lung volume (40% of total lung capacity (TLC) (most alveoli are collapsed, and the air is contained in overextended ducts. 2) Accordingly, the alveolar surface area-to-volume ratio is considerably smaller in particular at medium and low lung volumes. 3) There is only a slight change of mean air-space curvature between 80 and 40% TLC. Hence, the results indicate that in detergent-rinsed lungs volume changes are brought about predominantly by recruitment and derecruitment of alveoli. It appears that both a normal surfactant and the mechanical interdependence within the fibrous continuum are required to maintain a normal respiratory surface area within the lung volume range of normal breathing.
D000818:Animals; D066298:In Vitro Techniques; D008168:Lung / Q000502:physiology* / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011650:Pulmonary Alveoli / Q000648:ultrastructure; D011817:Rabbits; D013329:Structure-Activity Relationship; D014109:Total Lung Capacity
D011092:Polyethylene Glycols