Journal article
Rat alveolar epithelial cells concomitantly express plasminogen activator inhibitor-1 and urokinase
American journal of physiology. Lung cellular and molecular physiology, Vol.260(4), pp.L286-L295
04/01/1991
DOI: 10.1152/ajplung.1991.260.4.L286
PMID: 1902065
Abstract
There is considerable evidence to suggest that intra-alveolar plasminogen activation is instrumental in many aspects of inflammatory lung injury and subsequent tissue repair. Rat alveolar epithelial cells produce large quantities of urokinase-type plasminogen activator (uPA) in vitro, and uPA expression is modulated in association with cellular differentiation and exposure to inflammatory mediators. We now report that these cells also secrete heat-stable PA inhibitory activity having the characteristics of PA inhibitor type 1 (PAI-1). In particular, immunoreactive PAI-1 was demonstrable in conditioned media, cell lysates, and extracellular matrix from epithelial cell cultures. As alveolar epithelial cells differentiated in vitro, secreted PA inhibitor activity increased significantly from 104 +/- PAI U/ml (n = 5, mean +/- SE) on day 2 to 442 +/- 150 on day 7 in parallel with increases in secreted and matrix-associated immunoreactive PAI-1. PAI-1 mRNA expression decreased over this same period suggesting posttranscriptional regulation. The levels of both newly synthesized antigen and PAI-1 mRNA were increased by exposure to lipopolysaccharide and tumor necrosis factor-alpha. Thus, by the coexpression of uPA and PAI-1, the alveolar epithelium may actively regulate the generation of plasmin in both the normal and injured alveolus.
Details
- Title: Subtitle
- Rat alveolar epithelial cells concomitantly express plasminogen activator inhibitor-1 and urokinase
- Creators
- Thomas J Gross - Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109–0360Richard H Simon - Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109–0360Christopher J Kelly - Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109–0360Robert G Sitrin - Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109–0360
- Resource Type
- Journal article
- Publication Details
- American journal of physiology. Lung cellular and molecular physiology, Vol.260(4), pp.L286-L295
- DOI
- 10.1152/ajplung.1991.260.4.L286
- PMID
- 1902065
- ISSN
- 1040-0605
- eISSN
- 1522-1504
- Language
- English
- Date published
- 04/01/1991
- Academic Unit
- Pulmonary, Critical Care, and Occupational Medicine; Internal Medicine
- Record Identifier
- 9984094610002771
Metrics
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