Biomaterial Database

Effect of elastase and ventilation on elastic recoil of excised dog lungs. 1979

J K Polzin, and J S Napier, and J C Taylor, and J R Rodarte

The effect of porcine pancreatic elastase and mechanical ventilation on tissue elastic recoil was examined in excised dog lung lobes. Lobes incubated for one hour with an elastase-buffer mixture showed a significant (P less than 0.001) left shift of the liquid-filled pressure-volume curve at all pressures measured (0 to 12 cm H2O) when compared to lobes treated with buffer only. These results suggest that the contribution of elastin to the elastic properties of lung tissue is greatest at mid-lung volumes, but that it also contributes to delimiting maximal lung volume. Elastase and buff-treated lobes were inflated cyclically with humidified air to a pressure of 20 cm H2O 6 times per min during a 16-hour period. This mechanical ventilation caused no further decrease of tissue elastic recoil. Ventilation did cause an unexpected increase in the elastic recoil of liquid-filled lobes that was significant at pressures of 4 cm H2O (P less than 0.025) or more (P less than 0.001). Elastase and buffer-treated lobes showed an almost identical rightward shift of the pressure-volume curve after ventilation when compared to the respective nonventilated control lobes. This increased recoil cannot be attributed to altered surface tension.

UI	MeSH Term	Description	Entries
D008170	Lung Compliance	The capability of the LUNGS to distend under pressure as measured by pulmonary volume change per unit pressure change. While not a complete description of the pressure-volume properties of the lung, it is nevertheless useful in practice as a measure of the comparative stiffness of the lung. (From Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p562)	Compliance, Lung,Compliances, Lung,Lung Compliances
D008176	Lung Volume Measurements	Measurement of the amount of air that the lungs may contain at various points in the respiratory cycle.	Lung Capacities,Lung Volumes,Capacity, Lung,Lung Capacity,Lung Volume,Lung Volume Measurement,Measurement, Lung Volume,Volume, Lung
D010196	Pancreatic Elastase	A protease of broad specificity, obtained from dried pancreas. Molecular weight is approximately 25,000. The enzyme breaks down elastin, the specific protein of elastic fibers, and digests other proteins such as fibrin, hemoglobin, and albumin. EC 3.4.21.36.	Elastase,Pancreatopeptidase,Elastase I,Pancreatic Elastase I,Elastase I, Pancreatic,Elastase, Pancreatic
D011656	Pulmonary Emphysema	Enlargement of air spaces distal to the TERMINAL BRONCHIOLES where gas-exchange normally takes place. This is usually due to destruction of the alveolar wall. Pulmonary emphysema can be classified by the location and distribution of the lesions.	Emphysema, Pulmonary,Centriacinar Emphysema,Centrilobular Emphysema,Emphysemas, Pulmonary,Focal Emphysema,Panacinar Emphysema,Panlobular Emphysema,Pulmonary Emphysemas,Centriacinar Emphysemas,Centrilobular Emphysemas,Emphysema, Centriacinar,Emphysema, Centrilobular,Emphysema, Focal,Emphysema, Panacinar,Emphysema, Panlobular,Emphysemas, Centriacinar,Emphysemas, Centrilobular,Emphysemas, Focal,Emphysemas, Panacinar,Emphysemas, Panlobular,Focal Emphysemas,Panacinar Emphysemas,Panlobular Emphysemas
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D004195	Disease Models, Animal	Naturally-occurring or experimentally-induced animal diseases with pathological processes analogous to human diseases.	Animal Disease Model,Animal Disease Models,Disease Model, Animal
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013500	Surface Tension	The force acting on the surface of a liquid, tending to minimize the area of the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Interfacial Force,Interfacial Tension,Surface Tensions,Tension, Surface,Tensions, Surface