title: Protease inhibitors in rheumatoid synovial fluid. Analyses of electrophoretic homogeneity and protease inhibitory capacity.
abstract: Paired plasma and synovial fluids from 17 patients with seropositive rheumatoid arthritis were examined for electrophoretic homogeneity/heterogeneity and enzymic inhibitory capacity of the protease inhibitors. The high degree of saturation (approximately 90%) of the polyvalent protease inhibitor alpha 2-macroglobulin in the rheumatoid synovial fluid contrasts sharply with the low saturation of alpha 1-anti-trypsin. The inhibitory reactivity of the non-complexed fraction of both of these dominating antiproteases was retained (approximately 85-90%). Thus, a selective inactivation of synovial alpha 1-antitrypsin could not be demonstrated. alpha 1-Anti-chymotrypsin revealed electrophoretic homogeneity in all synovial fluids. Electrophoretic heterogeneity of the plasmin inhibitor antiplasmin was detected in the majority of synovial fluids indicating plasmin activation. The existence of a protease-antiprotease imbalance in the rheumatoid joint was indicated by the high degree of saturation of alpha 2-macroglobulin and a cleavage of C3 in rheumatoid synovial fluids.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D002918:Chymotrypsin / Q000032:analysis / Q000037:antagonists & inhibitors; D003176:Complement C3 / Q000032:analysis; D004586:Electrophoresis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011480:Protease Inhibitors / Q000032:analysis*; D013582:Synovial Fluid / Q000032:analysis*; D000514:alpha 1-Antichymotrypsin; D000515:alpha 1-Antitrypsin / Q000032:analysis; D000979:alpha-2-Antiplasmin / Q000032:analysis; D000511:alpha-Macroglobulins / Q000032:analysis
chemical_list: D003176:Complement C3; D011480:Protease Inhibitors; D000514:alpha 1-Antichymotrypsin; D000515:alpha 1-Antitrypsin; D000979:alpha-2-Antiplasmin; D000511:alpha-Macroglobulins; D002918:Chymotrypsin