[Proteolytic occurrences in the metabolism of cartilage and their modification by antirheumatics].

Rheumatic diseases are characterized by the progressive loss of articular cartilage. According to a well established hypothesis proteolytic enzymes take part in these events. The initial attack in an normal cartilage can be exerted by proteoglycanases originating from either chondrocytes or cells from outside the cartilage like neutrophilic granulocytes or macrophages. In rheumatoid arthritis these latter cells are found in immediate vicinity to cartilage and it is assumed that they release their enzymes directly into the cartilage. Lysosomal elastase from neutrophilic granulocytes is a key enzyme made responsible for the degradation of cartilage, since it is able to soften up this tissue and thereby to deprive it of its normal mechanical properties. Therefore the pharmacological inactivation of elastase bears a therapeutic potential for rheumatic joint disease. The ultimate value of enzyme inhibitory antirheumatic drugs needs, however, further investigation since also enzyme independent variables play an important role in maintaining normal function of cartilage.