title: Concentrations of elastinolytic metalloproteinases in respiratory tract secretions of healthy horses and horses with chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  To determine whether samples of tracheal epithelial lining fluid (TELF) obtained from horses have elastinolytic activity characteristic of metalloproteinases, to compare elastinolytic activity in TELF obtained from healthy horses and horses with chronic obstructive pulmonary disease (COPD), and to determine whether chemically modified tetracycline-3 (CMT-3) inhibits elastinolytic activity in TELF ANIMALS: 10 horses with COPD and 10 healthy control horses.
  
  
  METHODS
  Zymography and fluorometry were used to measure elastinolytic activity, and EDTA was used to inhibit elastinolytic activity and verify that the activity was attributable to metalloproteinases. Possible inhibition of elastinolytic activity with CMT-3 was studied in vitro.
  
  
  RESULTS
  Elastinolytic activity was found in TELF obtained from all horses, and this activity was significantly higher in TELF obtained from horses with COPD than in TELF obtained from healthy horses. For all samples, EDTA and CMT-3 inhibited elastinolytic activity.
  
  
  CONCLUSIONS
  Elastinolytic activity is detectable in TELF obtained from horses and seems to be attributable to metalloproteinases. Elastinolytic activity in TELF is significantly inhibited by CMT-3. Elastinolytic activity in TELF can be detected by means of zymography or fluorometry. Increased elastinolytic activity may reflect destruction of pulmonary tissue in horses with COPD. Chemically modified tetracyclines such as CMT-3 may provide an additional treatment possibility for horses with COPD.
authors.affiliation: Department of Clinical Veterinary Sciences, Faculty of Veterinary Medicine, Helsinki University, Finland.
authors.forename: S M
authors.initials: SM
authors.lastname: Raulo
authors.forename: T A
authors.initials: TA
authors.lastname: Sorsa
authors.forename: P S
authors.initials: PS
authors.lastname: Maisi
mesh_terms: D000818:Animals; D015536:Down-Regulation; D004492:Edetic Acid / Q000494:pharmacology; D004549:Elastin / Q000378:metabolism*; D005260:Female; D005470:Fluorometry / Q000662:veterinary; D006734:Horse Diseases / Q000201:enzymology*; D006736:Horses; D008173:Lung Diseases, Obstructive / Q000201:enzymology / Q000662:veterinary*; D008297:Male; D008970:Molecular Weight; D011480:Protease Inhibitors / Q000494:pharmacology; D012137:Respiratory System / Q000201:enzymology*; D013754:Tetracyclines / Q000494:pharmacology
chemical_list: D011480:Protease Inhibitors; D013754:Tetracyclines; C117155:tetracycline CMT-3; D004549:Elastin; D004492:Edetic Acid