| Abstrakt: |
Mammalian collagenases (EC 3,4,24.7) have been suggested as playing an essential role in the initiation of the collagen degradation in periodontal diseases. Two distinct types of interstitial collagenases have been characterized in vertebrate tissues. These enzymes, the fibroblast. and the neutrophil-type collagenases, differ in molecular weight and antigenic properties, as well as substrate specificity and mechanism of activation. In order to determine the cellular origin and mode of action of collagenase in periodontal tissue, we studied the molecular size, the substrate specificity and the activation of collagenases partially purified from inflamed human gingival extracts, sulcular fluid, gingival explant culture medium and polymorphonuclear leukocytes (PMN). Types I, II and Ill collagens used as substrates were purified from bovine tendon, cartilage and amnion membrane, respectively. Apparent molecular weights of 70 75 k were obtained for gingival extract, sulcular fluid and PMN collagenases and 45 k for gingival explant culture collagenase by gel filtration technique. The gingival extract and sulcular fluid collagenases as well as PMN collagenase could be activated by gold thioglucose and gold thiomalate; no activation of gingival explant culture collagenase was noted. The gingival extract collagenase, sulcular fluid collagenase and PMN collagenase degraded preferentially types I and II collagens relative to type-Ill collagen. In contrast, gingival explant culture collagenase degraded preferentially types I and Ill collagens relative to type-II collagen. The results indicate that collagenase in extracts of inflamed human gingiva and in sulcular fluid during inflammation is mostly derived from PMN cells. On the other hand, collagenase produced by gingival explants in culture is probably synthesized by fibroblasts. [ABSTRACT FROM AUTHOR] |
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