Concentration of interleukin-1 beta in serum and synovial fluid in patients with rheumatoid arthritis and those with osteoarthritis.

The concentration of interleukin-1 beta (IL-1 beta) in serum and synovial fluid of the knee of patients with rheumatoid arthritis (RA) and those with osteoarthritis (OA) was examined using a recently developed radioimmunoassay method. The serum concentration of IL-1 beta was below the detection limit of 0.25 ng/ml in all RA and OA patients. The IL-1 beta concentration in the synovial fluid was higher in RA patients than in OA patients. In RA patients, a significant correlation was demonstrated between the synovial fluid IL-1 beta concentration and the erythrocyte sedimentation rate, C-reactive protein level, synovial fluid white blood cell count and Lansbury index. The synovial fluid IL-1 beta concentration decreased with the reduction of the rheumatoid activity by the medication, but tended to increase or remain high when inflammatory activity of RA could not be adequately controlled. The IL-1 beta concentration, easily determined, shows promise as a new quantitative indicator of rheumatoid activity.

[Influence of intraarticular continuous perfusion of physiological saline on chondrocytes].

Physiological saline, which is generally used in arthroscopic examination and operation, is not physiological in the synovial joints. This paper discusses metabolic changes in the articular cartilage following continuous intraarticular perfusion with physiological saline, in comparison with in vitro findings. Fourty rabbits weighing approximately 3 kg were intraarticularly and continuously perfused with saline at a rate of 250 ml/hour. Articular cartilage of the femoral condyle was collected for measurement of 35SO4 radioactivity by liquid-scintillation spectrometry. Incorporation of 35SO4 showed increment in perfused articular cartilage as compared with the controls after one hour. Namely, glycosaminoglycan synthesis of chondrocytes was accelerated temporarily by continuous perfusion of saline, and it was recovered twenty-four hours after perfusion. In addition, histological and biomechanical test showed no remarkable changes. But, these effects will be expanded by the presence of degenerated articular cartilage. Continuous perfusion of physiological saline changes the physiological circumstance for articular cartilage, and influences on the chondrocytes' metabolism temporarily.