Variations in cartilage catabolism in different equine joints in response to interleukin-1 in vitro

An explant system was used to investigate the hypothesis that cartilage fro m different equine joints might respond differently to challenge with inter leukin-1 alpha (IL-1 alpha). Pairs of normal cartilage samples were taken f rom the metacarpophalangeal, proximal interphalangeal and distal interphala ngeal joints of six horses. One of each pair was stimulated with 10 ng/ml h uman recombinant IL-1 alpha for three days, and the supernatants and remain ing cartilage explants were analysed for their total content of glycosamino glycans. A significantly higher percentage of glycosaminoglycans was releas ed from the cartilage of the proximal and distal interphalangeal joints tha n from the metacarpophalangeal joint.