Cholesterol in Connective Tissue of Joints

Abstract

Lipids are present in most connective tissues. Rheumatoid arthritis (RA) patients have high synovial and low serum cholesterol concentrations and occasional cholesterol crystal deposition. To ascertain whether tritium-labeled cholesterol is transported into connective tissues, H³-cholesterol was injected into rabbit knees. It was found to enter cartilage and synovium, counts remaining above background for 40 days. Cholesterol crystals injected similarly, produced acute synovitis, lasting at least 20 days. H³-cholesterol was injected into a cholesterol-crystal-forming RA patient's knee; H³-cholesterol remained in synovial fluid above background level counts for 10 days.