title: Neutrophil proteinases in hydrochloric acid- and endotoxin-induced acute lung injury: evaluation of interstitial protease activity by in situ zymography.
abstract: We investigated the role of polymorphonuclear neutrophil (PMN) proteinases, elastase, and gelatinase B in rat models of acute lung injury. Three groups of rats were studied 6 hours after unilateral instillation of hydrochloric acid (HCl; 0.1 N), lipopolysaccharide (LPS) (4 microg), or saline. The results demonstrated that HCl-induced lung injury, as compared with LPS-induced lung injury, was associated with an increase in permeability (wet/dry weight ratio and proteins in bronchoalveolar lavage fluid). In contrast, there was similar PMN recruitment (in bronchoalveolar lavage fluid and myeloperoxidase activity in lung homogenates) and similar proteinase exocytosis (residual alveolar PMN content of elastase and gelatinase B) in both types of lung injury. In situ zymography, evaluating interstitial protease/inhibitor balance, demonstrated a decrease in gelatinolytic activity in both HCl- and LPS-injured lungs compared with normal lung. The increase in interleukin 6 concentration in lung homogenates, which is observed after both injuries compared with saline-instilled animals, could be involved in up-regulation of tissue inhibitor of matrix metalloproteinase-1, shown by immunocytochemistry to participate in antiproteinase excess. Neither inhibition of alveolar neutrophil influx using a leukocyte elastase inhibitor (EPI-hNE-4) nor inhibition of gelatinase activities by recombinant adenovirus for the human tissue inhibitor of matrix metalloproteinase 1 gene transfer decreased lung edema in HCl-induced injury. These data suggest that PMN proteinases do not contribute to HCl-induced acute lung injury in rats.
authors.affiliation: INSERM U 492, Université Paris XII, France.
authors.forename: Andry
authors.initials: A
authors.lastname: Van de Louw
authors.forename: Daniel
authors.initials: D
authors.lastname: Jean
authors.forename: Eric
authors.initials: E
authors.lastname: Frisdal
authors.forename: Charles
authors.initials: C
authors.lastname: Cerf
authors.forename: Marie-Pia
authors.initials: MP
authors.lastname: d'Ortho
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Baker
authors.forename: Chantal
authors.initials: C
authors.lastname: Lafuma
authors.forename: Philippe
authors.initials: P
authors.lastname: Duvaldestin
authors.forename: Alain
authors.initials: A
authors.lastname: Harf
authors.forename: Christophe
authors.initials: C
authors.lastname: Delclaux
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid; D010450:Endopeptidases / Q000378:metabolism*; D004731:Endotoxins / Q000633:toxicity*; D004791:Enzyme Inhibitors / Q000378:metabolism; D018014:Gene Transfer Techniques; D006851:Hydrochloric Acid / Q000633:toxicity*; D007150:Immunohistochemistry; D015850:Interleukin-6 / Q000378:metabolism; D008168:Lung / Q000201:enzymology / Q000378:metabolism; D008171:Lung Diseases / Q000139:chemically induced / Q000201:enzymology*; D009504:Neutrophils / Q000201:enzymology*; D051381:Rats; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D004731:Endotoxins; D004791:Enzyme Inhibitors; D015850:Interleukin-6; D019715:Tissue Inhibitor of Metalloproteinase-1; D014409:Tumor Necrosis Factor-alpha; D010450:Endopeptidases; D006851:Hydrochloric Acid