You are looking at 1 - 4 of 4 items for
- Author or Editor: Päivi S. Maisi x
- Refine by Access: All Content x
Objectives—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.
Procedure—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 and Clinical Relevance—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. (Am J Vet Res 2000;61:1067–1073)
Objectives—To determine collagenase activity and evaluate matrix metalloproteinase (MMP)-8 and MMP-13 in horses with chronic obstructive pulmonary disease (COPD).
Animals—12 horses with COPD and 12 healthy control horses.
Procedure—Collagenase activity was determined by use of an assay for degradation of type-I collagen. Western immunoblot analysis was used to identify interstitial collagenases MMP-8 and MMP-13 in tracheal epithelial lining fluid (TELF). Immunocytochemistry and in situ hybridization were used to determine cellular expression of these 2 collagenases in cells in bronchoalveolar lavage fluid (BALF).
Results—Collagenase activity was approximately 7 times higher in samples obtained from horses with COPD, compared with control horses. During stabling, horses with COPD had significantly higher collagenase activity than after being maintained on summer pasture, when activity was similar to that of control horses. Immunoreactivity of MMP-8 and MMP-13 was significantly increased in TELF of horses with COPD, compared with healthy horses. In TELF, a positive correlation was detected between immunoreactivity of MMP-8 and MMP-13 and the amount of degradation of type-I collagen. Macrophages and epithelial cells were the major cellular sources of MMP-8 and MMP-13.
Conclusions and Clinical Relevance—Increased collagenase activity in TELF indicates active ongoing disease and, thus, may reflect lung tissue changes in horses with COPD. Measurements of collagenase activity and MMP immunoreactivity may provide additional diagnostic tools to identify the active phase of chronic lung disease. (Am J Vet Res 2001;62:1142–1148)
Objective—To study gelatinolytic matrix metalloproteinases (MMPs) in tracheobronchial lavage fluid (TBLF) obtained from clinically normal calves and calves with Pasteurella multocida infection.
Sample Population—Samples of TBLF obtained from 11 calves with clinical signs of respiratory tract disease and growth of P multocida and Mycoplasma spp during culture of TBLF and samples of TBLF from 6 clinically normal calves with no bacterial growth during culture of TBLF.
Procedure—MMPs in TBLF were analyzed by use of gelatin zymography. Gelatinases were identified on the basis of molecular weights and inhibition by EDTA.
Results—The main gelatinolytic MMPs detected were the proform (90 to 110 kd) and active form (75 to 85 kd) of MMP-9 (gelatinase B) and the proform (67 to 75 kd) and active form (< 65 kd) of MMP-2 (gelatinase A). Increased amounts of active MMP-2 and MMP-9 were detected in TBLF of calves with respiratory tract disease, compared with amounts of active MMP-2 and MMP-9 in TBLF of clinically normal calves. Concurrent infection with Mycoplasma bovirhinis in calves with pneumonia attributable to P multocida was associated with higher concentrations of MMP-9.
Conclusions and Clinical Relevance—The host response to P multocida includes increases in MMP-2 and MMP-9 concentrations in TBLF. Greater amounts of MMPs detected in calves with concurrent M bovirhinis and P multocida infection indicates synergism between these organisms. (Am J Vet Res 2005;66:2101–2106)
Objective—To determine reference values for cytologic examination results of bronchoalveolar lavage fluid (BALF) and to investigate effects of repeated lavages on pulmonary health and on results of cytologic examination of BALF in dogs.
Animals—16 healthy adult Beagles.
Procedure—All dogs underwent pulmonary lavage to obtain BALF. Eleven dogs were repeatedly lavaged 6 times at 5– to 7–week intervals. Analyses for total and differential cell counts and for viability of cells before and after cell processing were performed. Arterial blood gas analysis before and after bronchoalveolar lavage was used to study the safety of the lavage procedure. Histologic and radiologic examinations were used to study effects of repeated lavages on pulmonary health.
Results—Mean (± SD) cell count was 104 ± 69 cells/µl, comprising 75 ± 7% alveolar macrophages, 13 ± 6% lymphocytes, 5 ± 4% neutrophils, 4 ± 5% eosinophils, 2 ± 2% mast cells, 0.6 ± 0.7% epithelial cells, and 0.3 ± 0.4% plasma cells. Centrifugation of samples and washing of cells caused significant cell loss (59 ± 13%). Repeated lavages did not cause significant variations in cell counts of BALF or results of arterial blood gas analysis, thoracic radiography, or histologic examination of pulmonary specimens. Only a moderate, although significant, decrease in arterial oxygen content was observed after bronchoalveolar lavage.
Conclusions and Clinical Relevance—Analysis indicated that several lavages performed at 5– to 7–week intervals can safely and reliably be used to study the kinetics of pathologic processes in pulmonary tissues or for evaluation of therapeutic efficacy. (Am J Vet Res 2001;62:13–16)