Release of glycosaminoglycans into the culture medium following an impact load on articular cartilage explants. Explants of human articular cartilage were impact loaded with a mass of 500 g dropped from 25 mm (0.13 J). The culture medium from each explant was collected at 3 days and 6 days following loading. The concentration of GAGs in the medium was measured with the DMMB assay, normalised to the wet weight of each explant and expressed per mg of cartilage. Day 6 results represent the cumulative release of GAGs (combining the two 3-day periods). Mean values (± standard deviation, n = 3) from three experiments are shown. Each experiment used five replicates in each group. (a) Impact load significantly increased the concentration of GAGs in the explant culture medium. Asterisks denote significant differences (**p ≤ 0.01) between unloaded controls and impact loaded explants. (b) The release of GAGs was unaffected by the addition of celecoxib or indomethacin.