Influence of development and joint pathology on stromelysin enzyme activity in equine synovial fluid

OBJECTIVE To investigate the role of stromelysin (MMP-3) activity in synovial fluid (SF) at different stages of development and in common joint disorders in the horse. METHODS Stromelysin activity was determined with a fluorogenic enzyme activity assay in SF of normal joints of fetal, juvenile and adult horses, and in SF of horses suffering from the developmental orthopaedic disease osteochondrosis (OC) or osteoarthritis (OA). Additionally, MMP-3 activity was expressed as a ratio of previously reported general MMP activity in the same SF samples. RESULTS The levels of active stromelysin were 30-fold to 80-fold higher in SF from fetal horses than in SF from juvenile and mature animals (p