Remodeling of alveolar walls after elastase treatment of hamsters. Results of elastin and collagen mRNA in situ hybridization.

Treatment of hamster lungs with porcine pancreatic elastase (PPE) causes emphysema and a decrease in lung elastin content, which returns to control level by Day 30. To explore the mechanism of alveolar wall remodeling after elastolytic injury, we examined the expression of elastin and alpha1(I) collagen mRNAs by in situ hybridization at 1, 2, 3, 5, 7, and 30 d after intratracheal PPE. The lungs of control animals displayed weak signals for elastin and alpha1(I) collagen mRNA in pleura, large arteries, veins, and airways. There was little or no signal in respiratory air space walls. Increased expression of elastin and alpha1(I) collagen mRNA began by Day 1 after PPE and reached an asymptote by Day 3 that was maintained by elastin until Day 7; expression of alpha1(I) collagen mRNA waned earlier. Elastin and, to a lesser extent, alpha1(I) collagen mRNA were heavily expressed in pleura, blood vessels, and airways. Analysis of serial sections showed elastin message was minimal in the walls of respiratory air spaces and when present, at 3, 5, and 7 d, was primarily found at the free margins of alveolar septa. Collagen message was very sparse in respiratory air space walls. By 30 d, elastin mRNA expression was reduced but still above control levels and emphysema was widespread and severe. Rank score of elastin mRNA expression in individual subpleural air spaces showed a positive correlation with air space size. In conclusion, most expression of elastin and alpha1(I) collagen mRNA occurs in the pleura, airway, and vascular walls. In respiratory air space walls, expression of elastin mRNAs occurs in damaged tissue at free septal margins.

[1]  C. Kuhn,et al.  The effect of oxygen on Cor pulmonale in experimental emphysema induced by elastase or elastase and beta-aminopropionitrile in hamsters. , 2015, American Review of Respiratory Disease.

[2]  E. Lucey,et al.  Differing susceptibility of young and adult hamster lungs to injury with pancreatic elastase. , 2015, American Review of Respiratory Disease.

[3]  B. Starcher,et al.  The effect of lathyrogens on the evolution of elastase-induced emphysema. , 2015, The American review of respiratory disease.

[4]  G. Snider,et al.  Internal surface area and number of respiratory air spaces in elastase-induced emphysema in hamsters. , 2015, American Review of Respiratory Disease.

[5]  G. Snider,et al.  Distribution of Elastin in Hamsters and the Turnover Rates of Different Elastin Pools , 1997, Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine.

[6]  D Lamb,et al.  Collagen content of alveolar wall tissue in emphysematous and non-emphysematous lungs. , 1994, Thorax.

[7]  W. Thurlbeck,et al.  Collagen and elastin in human pulmonary emphysema. , 1993, The American review of respiratory disease.

[8]  Y. Okada,et al.  Collagenase expression in the lungs of transgenic mice causes pulmonary emphysema , 1992, Cell.

[9]  B. Gu,et al.  Effect of ohmic contact conductance on the distribution of surface and bulk currents in semiconductor planar devices , 1992 .

[10]  A. Fine,et al.  Discordant regulation of human type I collagen genes by prostaglandin E2. , 1992, Biochimica et biophysica acta.

[11]  J. Crapo,et al.  Structural changes in elastic fibers after pancreatic elastase administration in hamsters. , 1992, Journal of applied physiology.

[12]  D. Rowe,et al.  Differential utilization of regulatory domains within the alpha 1(I) collagen promoter in osseous and fibroblastic cells , 1992, The Journal of cell biology.

[13]  J A Pierce,et al.  Marked longevity of human lung parenchymal elastic fibers deduced from prevalence of D-aspartate and nuclear weapons-related radiocarbon. , 1991, The Journal of clinical investigation.

[14]  J. Foster,et al.  Characterization of rat heart tropoelastin. , 1989, Archives of biochemistry and biophysics.

[15]  G. Snider,et al.  Cadmium-chloride-induced air-space enlargement with interstitial pulmonary fibrosis is not associated with destruction of lung elastin. Implications for the pathogenesis of human emphysema. , 1988, The American review of respiratory disease.

[16]  H. Kagan,et al.  Ultrastructural changes in hamster lung 15 min to 3 hr after exposure to pancreatic elastase , 1986, The Anatomical record.

[17]  M. Dubick,et al.  Elastin metabolism and chemistry: potential roles in lung development and structure. , 1984, Environmental health perspectives.

[18]  G. Snider,et al.  Ultrastructural changes in hamster lung four hours to twenty‐four days after exposure to elastase , 1981, The Anatomical record.

[19]  M. Kinjo,et al.  Ultrastructural studies of elastase-induced experimental emphysema. , 1979, The Japanese journal of experimental medicine.

[20]  G. Snider,et al.  A one-year study of the evolution of elastase-induced emphysema in hamsters. , 1977, Journal of applied physiology: respiratory, environmental and exercise physiology.

[21]  R. Senior,et al.  The induction of emphysema with elastase. II. Changes in connective tissue. , 1976, Laboratory investigation; a journal of technical methods and pathology.

[22]  G. Snider,et al.  The pathology of elastase‐induced panacinar emphysema in hamsters , 1975, The Journal of pathology.

[23]  R. R. Wright.  Elastic tissue of normal and emphysematous lungs. A tridimensional histologic study. , 1961, The American journal of pathology.

[24]  A. Churg,et al.  Smoke-induced emphysema in guinea pigs is associated with morphometric evidence of collagen breakdown and repair. , 1995, The American journal of physiology.

[25]  J. Kleinerman,et al.  The effect of elastase on pulmonary elastin and collagen: comparison of intravenous and intratracheal exposure. , 1980, Experimental lung research.

[26]  G. Snider,et al.  Animal models of emphysema. , 1978, The American review of respiratory disease.

[27]  C. Kuhn,et al.  The scanning electron microscopy of elastase-induced emphysema. A comparison with emphysema in man. , 1976, Laboratory investigation; a journal of technical methods and pathology.