Daily injection of a crude papain solution into the knee joint of young rabbitst continued over a six day period resulted in a degeneration of the articular cartilage within two weeks. The initial findings were elevation and loosening of the cartilage in the weight bearing area followed by thinning and fibrillation of the remaining surface. Microscopic changes consisted of disruption of the cartilage adjacent to the subchondral bone and loss of the superficial layers. Changes in the articular cartilage were similar to changes seen in clinical forms of degenerative arthritis.
Le injection diurne de un solution de papaina crude ad in le articulation genicular de juvene conilios, quando continuate durante sex dies, resultava intra duo septimanas in un degeneration del cartilagine articular. Le constatationes initial esseva elevation e distachamento del cartilagine in le in areas sub pression de peso, sequite de tenuifi cation e fibrillation del remanente superficie. Le alterationes microscopic que esseva notate consisteva de disruption del cartilagine adjacente a1 osso subchondral con perdita del stratos superficial. Alterationes in le cartilagine articular esseva simile a alterationes vidite in formas clinic de arthritis degenerative.
ANY ATTEMPTS have been made to duplicate in the experimental ani-M mal varieties of joint disease found in man. A recent survey by Gardnerl on the experimental production of arthritis produced an extensive list of techniques and agents which have been used with varying degrees of success. Some of these efforts have produced forms of arthritis with features analogous to clinical but many variables have made it difficult to draw significant conclusions. Continued work is being done to find methods for inducing pathologic joint changes which will shed light on the etiology of chronic articular disease.
Intra-articular papain was selected in the present investigation to alter the composition of articular cartilage. Papain, a proteolytic enzyme, has a profound effect on cartilage in young animals when administered intravenou~ly.~ This effect has been related to the release of mucopolysaccharide from cartilage matrix without apparent alteration of the collagena6 Because of this specific activity it was felt that local injection might provide information as to the relative roles of mucopolysaccharide, collagen and cellular elements in maintaining joint cartilage integrity.