Characterization of chondrocytes from bovine articular cartilage: I. Metabolic and morphological experimental studies

Articular chondrocytes were enzymatically isolated from mature bovine cartilage and separated by density zone-velocity sedimentation in a gradient. For cells from different levels of the gradient, size and staining characteristics were determined and rates of incorporation of tritiated cytidine and radiosulphate were measured as indicators of RNA and sulphated glycosaminoglycan synthesis, respectively. The data clearly show that the chondrocyte population is composed of cells that vary continuously in size and metabolic activity from one limit to another. The largest cells also demonstrated the greatest RNA production while the smallest cells had the least. There was, however, no such differentiation of sulphated proteoglycan production.