Increased 92 kD gelatinase activity from alveolar macrophages in newborn rats
| Autor: | Alain Harf, M P D'Ortho, Christophe Delacourt, Chantal Lafuma, Sophie Pezet, I. Macquin-Mavier |
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| Rok vydání: | 1995 |
| Předmět: |
Male
Pulmonary and Respiratory Medicine medicine.medical_specialty Immunoblotting Matrix Metalloproteinase Inhibitors Lung injury Critical Care and Intensive Care Medicine Rats Sprague-Dawley Internal medicine Macrophages Alveolar medicine Animals Gelatinase Zymography Glycoproteins Lung medicine.diagnostic_test business.industry Metalloendopeptidases Tissue Inhibitor of Metalloproteinases Stimulation Chemical Rats Endocrinology Bronchoalveolar lavage medicine.anatomical_structure Animals Newborn Gelatinases Immunology Chromatography Gel Collagenase Tetradecanoylphorbol Acetate Interstitial collagenase Electrophoresis Polyacrylamide Gel Female Pulmonary alveolus business Bronchoalveolar Lavage Fluid medicine.drug |
| Zdroj: | American Journal of Respiratory and Critical Care Medicine. 151:1939-1945 |
| ISSN: | 1535-4970 1073-449X |
| DOI: | 10.1164/ajrccm.151.6.7767543 |
| Popis: | The functional immaturity of neonatal alveolar macrophages (AM) may contribute to the increased susceptibility of neonates to lung injury. Because the secretion of proteinases by neonatal AMs may be involved in normal postnatal lung development and in repair after lung injury, we evaluated the capacity of neonatal AMs to secrete 92 kD Type IV collagenase. AMs were obtained by bronchoalveolar lavage from newborn rats at different postnatal ages. Total gelatinase activity was measured by zymography in AM-conditioned media. Spontaneous secretion of gelatinase from AMs varied significantly with age, the highest levels being found immediately after birth. Stimulation of AMs by PMA induced a four- to fivefold greater increase in total gelatinase activity during the first 10 d of postnatal life compared with adulthood. Using [3H]gelatin as the substrate, we found high free gelatinase activity only within 24 h after birth; data obtained after exposing cells to natural surfactant suggested that surfactant may account in part for this increase in free gelatinase activity. No secretion of tissue inhibitor of metalloproteinases (TIMP) by AMs was detectable in newborns within 24 h after birth. We conclude that AMs from newborn rats are able to secrete more gelatinase than AMs from adults, and this enzyme production profile during the neonatal period may contribute to the fact that newborns with lung injury are at high risk for extracellular matrix degradation. |
| Databáze: | OpenAIRE |
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