INCREASE OF FREE COLLAGENASE AND NEUTRAL PROTEASE ACTIVITIES IN THE GINGIVAL CREVICE DURING EXPERIMENTAL GINGIVITIS IN MAN

Free activities of collagenase and neutral protease were measured in the gingival washings collected with individual appliances before, during and after a 21-day period of experimental gingivitis in 8 male subjects who refrained from tooth-brushing. Collagenase was determined by measuring the release of soluble radioactivity from3H-labelled, reconstituted collagen fibrils and neutral protease by measuring the breakdown of haemoglobin. The concentration of collagenase and neutral protease increased significantly during abstention from tooth-brushing, as did the specific activities of the two enzymes (free enzyme activity/number of polymorphonuclear (leukocytes). SDS-polyacrylamide gel electrophoresis of the digestion products of native collagen mixed with concentrated gingival washings showed that the collagenase in the gingival crevice is partly of mammalian origin. The inhibition study with serum and EDTA suggested a minor contribution of bacterial collagenase. © 1979.