GELATINOLYTIC ACTIVITY IN TRACHEAL EPITHELIAL LINING FLUID AND IN BLOOD FROM HORSES WITH CHRONIC OBSTRUCTIVE PULMONARY-DISEASE

Objectives-To determine whether gelatinolytic activity in tracheal epi thelial lining fluid (TELF), blood neutrophils, and blood lymphocytes from horses was metalloprotease activity, and to compare, for healthy horses and horses with chronic obstructive pulmonary disease, gelatino lytic activity in neutrophils, lymphocytes, and serum with activity in TELF. Animals-7 horses with chronic obstructive pulmonary disease (CO PD) and 4 healthy control horses. Procedure-Neutrophils and lymphocyte s were obtained by means of Percoll separation. Zymography was used to detect gelatinolytic activity; EDTA inhibition and 4-aminophenyl merc uric acetate activation were used to verify that gelatinolytic activit y was metalloprotease activity, Results-Gelatinolytic activity was sig nificantly higher in TELF from horses with COPD than in TELF from heal thy horses. For all samples, EDTA inhibited and APMA activated gelatin olytic activity. Gelatinolytic activity of neutrophils, lymphocytes, a nd serum was not significantly different between healthy horses and ho rses with COPD. Conclusions-Results suggested that gelatinolytic activ ity in TELF from horses is metalloprotease activity. Gelatinolytic act ivity is increased in TELF from horses with COPD, but not in serum, ne utrophils, or lymphocytes. Neutrophils and lymphocytes are possible so urces of gelatinolytic activity in TELF. Clinical Relevance-Measuremen ts of serum, blood neutrophil, or blood lymphocyte gelatinolytic activ ity were of little value in distinguishing horses with COPD from healt hy horses.