PLASMA AND SYNOVIAL-FLUID LYSOZYME ACTIVITY IN HORSES WITH EXPERIMENTAL CARTILAGE DEFECTS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 40  (11) , 1531-1536
Abstract
Cartilaginous defects were created in the radiocarpal joints of 12 horses. Synovial fluid cytologic features, lysozyme activity and .beta.-glucuronidase activity were monitored for 16 days. A comparison was made of plasma lysozyme and .beta.-glucuronidase activity and of synovial fluid lysozyme, .beta.-glucuronidase and leukocyte concentrations. Plasma lysozyme was independent of synovial fluid lysozyme activity. Synovial fluid lysozyme was significantly increased (P < 0.001) in all joints with surgically induced defects (group I) compared to controls (arthrocentesis done; group III). There was no significant difference in lysozyme activity in group I joints and sham-operated controls (cartilage exposed only; group II). Increased lysozyme concentration was positively correlated with increased numbers of leukocytes in the synovial fluid. Parallel changes were noted in synovial fluid .beta.-glucuronidase activity, indicating that much of the observed synovial fluid lysozyme activity was of lysosomal origin and not from cartilage destruction. Lysozyme activity in synovial fluid was a very sensitive indicator of acute joint injury, inflammation or both.