Hyaluronic acid and hyaluronidase activity in gingival exudate from sites of acute ulcerative gingivitis in man.

Gingival exudates from sites of acute ulcerative gingivitis (AUG) and chronic gingivitis (CG) in adults were investigated by cellulose-acetate electrophoresis for the hyaluronic acid (HA) content and assayed for the levels of HA-degrading enzymes. HA was the only glycosaminoglycan (GAG) in gingival exudate from CG sites. HA was not detected at untreated AUG sites but was evident, at increasing levels, after two and seven days of effective antibacterial treatment. In AUG exudates, the total HA-degrading enzyme activity, of bacterial origin, decreased to approx. 30 and 10 per cent of the high initial levels after two and seven days of treatment respectively, to that level found at sites of CG. The specific activity of HA-degrading enzyme of lysosomal origin was low initially and increased with treatment to a level comparable to CG. The notable absence of HA from gingival exudate from sites of untreated AUG thus appears to result from the increased levels of bacterial hyaluronidase. Electrophoresis of gingival exudate may be an indirect method of monitoring the rate of response of AUG to different antibacterial treatments.