SUBSTANCE-P AND NEUROKININ-A IN GINGIVAL CREVICULAR FLUID IN PERIODONTAL HEALTH AND DISEASE

The aims of the present study were to investigate whether the tachykin ins substance P and neutokinin A were present in gingival crevicular f luid in both periodontal health and disease and to study the relations hip with periodontal inflammation. Gingival crevicular fluid (GCF) was collected from a healthy, a gingivitis and a periodontitis site in 20 subjects with periodontitis and from a healthy site in 20 subjects wi thout periodontitis. The volume of GCF was measured and each sample su bsequently analysed for substance P and neurokinin A by radioimmunoass ay. There were significantly increased levels of substance P-like immu noreactivity (SP-LI) and neurokinin A-like immunoreactivity (NKA-LI) i n gingivitis and periodontitis sites compared with healthy sites. Both tachykinins were significantly elevated in periodontitis affected sub jects, with significantly more tachykinin-like immunoreactivity at hea lthy sites in periodontitis affected compared with periodontally-healt hy subjects. Despite the considerable individual variation in the leve ls of SP-LI and NKA-LI, both tachykinins were present at levels at whi ch they could have biological activity. It is concluded that substance P and neurokinin A may have a role in the pathogenesis of periodontal disease and that further investigations could prove useful in clarify ing the mechanisms through which neuropeptides could modulate periodon tal health and disease.