Pathogenetic and Clinical Studies in Rheumatoid ArthritisPart Ⅰ: Enzymological Observation on Serum, Synovial Fluid and Synovial Membrane in Patients with Rheumatic Disease

The activities of four enzymes …… lactic dehydrogenase (LDH) with its isozymes, beta-glucuronidase (beta-G) with its isozymes, acid and alkaline phosphatases, were studied in serum, synovial fluid and synovial membrane obtained from 45 patients with rheumatoid arthritis (RA) and 17 patients with osteoarthritis (OA). The control group comprised sera from 20 normal subjects, synovial fluid and membrane from 10 patients who had no clinical evidence of joint disease prior to death and leukocytes isolated from normal human peripheral blood. The LDH isozyme was identified five fractions by means of agar gel electrophoresis, and the beta-G isozyme was shown to be composed of three fractions by the method using DEAE Sephadex A-50 column chromatography: beta-G Ⅰ activity in serum has been localized in gam maglobulin, beta-G Ⅱ in beta-globulin, and beta-G Ⅲ in alpha 1, alpha 2-globulin and albumin regions. In the present study, the author obtained the results as follows. 1) The activities of LDH, beta-G and acid phosphatase in synovial fluid from RA patients were extremely increased and significantly higher than from OA patients or cadavers, but alkaline phosphatase activity remained in low level. 2) The total LDH activity in rheumatoid synovial fluid was 1640u/ml, and 473u/ml in rheumatoid serum (P