Biosynthetic response of cartilage explants to dynamic compression

Abstract

The biosynthetic response of calf articular cartilage explants to dynamic compression testing was studied over a wide range of loads. The rates of glycosaminoglycan synthesis were determined by 35 S-sulphate assimilation, whereas amino acid uptake and protein synthesis was measured by 3 H-proline assay. Two culture chambers allowed uniaxial radially compression and mechanical testing of cartilage disks. Static biosynthetic components were measured via (1) 12 h compression whilst dynamic biosynthetic were calculated via (2) kinetic studies of a single compression followed by release (3) slow cycles of compression and release (4) oscillations superimposed Dynamic stiffness measurements identifi ed low and high frequency regimes in which different fl ow and deformation phenomena predominated. At low frquencies, signifi cant fl uid was exuded from the cartilage disks, whereas at high frequencies hydrostratic pressure increased within disks.