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 radiosulfate were measured as indicators of RNA and sulfated 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 sulfated proteoglycan production. The data reported here provide an essential baseline in terms of the variations in size and metabolic activity observed in normal chondrocyte populations. This information can be used to: (1) reveal changes in the characteristics of chondrocytes from diseased cartilage, and (2) identify subpopulations of chondrocytes with altered functions in normal or diseased articular or epiphyseal growth-plate cartilage when studying clinical problems related to cartilage.
ASJC Scopus subject areas
- Orthopedics and Sports Medicine