Nonactivatability of latent proteoglycanases in intact adult articular cartilage

Para-aminophenylmercuric acetate activates collagenases and proteoglycanases in vitro only in cartilage plugs but not in intact articular cartilage. This suggests that activation of latent proteoglycanases is only possible after damage of the tissue's integrity. Therefore isolated plugs of cartilage seem not to be suitable for determining proteoglycan turnover. For these investigations we propose the use of intact joint areas from whole half-joints.