Bradykinin Activity in Gingival Fluid: A Pilot Study

It may be possible to determine the degree of inflammation in gingival tissue by measuring the bradykinin levels in gingival fluid. Lewis (Ann NY Acad Sci 104:236, 1963) has demonstrated that bradykinin is a likely mediator in the inflammatory response. Salivary kallikrein activity (SALLAY and NADOR, J Dent Res 29: 232-236, 1950) and kininase activity (EIGEN ET AL, IADR Program and Abstracts of Papers, No. 301, 1966) increase with an increase in the severity of periodontitis. A positive relationship exists between gingival tissue bradykinin activity and degree of chronic gingivitis and periodontitis (RODIN ET AL, J Periodontol 43:476480, 1972). In patients with periodontosis, salivary kallikrein activity has been observed to be five to six times greater than in control patients of the same age (SALLAY and NADOR, 1950). The present study is a double-blind investigation to show the degree of bradykinin activity in gingival fluid from regions of periodontitis and periodontosis in humans. Periodontosis was complicated by periodontitis and was defined as a condition with appreciable radiographic alveolar bone loss around the permanent teeth of an apparently healthy young adult. Advanced bone loss could not be accounted for adequately by local factors. Clinical evaluations of gingival inflammation were based on the Gingival Index of Lde (J Periodontol 38:610, 1967). All gingival fluid was taken from posterior maxillary interproximal regions, which were isolated carefully to prevent contamination by saliva. The method of fluid collection and equipment have been described previously (KASLICK ET AL, J Dent Res 47:1192, 1968). Glass capillary tubes* with an internal diameter of 0.635 mm and outer diameter of 1.219 ± 0.025 mm were used for fluid collection. After collection, the undiluted supernatant gingival fluid was expelled immediately from the collection tubes and infused directly into a muscle bath preparation. The rat uterus contraction technique was used to determine bradykinin activity with a physiograph and an iso-