ACID PHOSPHATASE ACTIVITY IN RHEUMATOID SYNOVIA

Abstract

Abstract The synovial membranes from two normal joints, five joints affected by rheumatoid arthritis and two joints showing osteoarthritis were studied immediately after synovectomy. Marked differences in acid phosphatase activity were noted, the activity in rheumatoid synovia being twice as high as in the other two groups. The granular fraction, obtained by centrifugation, showed a 28‐fold increase in acid phosphatase activity as compared with the original whole homogenate of normal synovia. In rheumatoid arthritis, on the other hand, there was an only twofold increase. The significance of this finding from the standpoint of the rheumatoid tissue reaction is not clear, but the results seem to show that the lysosomal membranes of the reumatoid tissue were fragile. It should be borne in mind that agents which stabilize the lysosomal membrane have been shown to have a clinical effect on rheumatoid arthritis.