title: Effect of topical cimetidine rinse on gingival crevicular neutrophil leukocyte function.
abstract: BACKGROUND
  Three coordinated mechanism-of-action clinical studies were conducted to examine the effects of topical cimetidine rinse on neutrophil function in the gingival crevice.
  
  
  METHODS
  The first study was a randomized, double-blind, placebo-controlled, 28-day experimental gingivitis study involving 21 healthy adults, in which subjects rinsed twice a day with placebo or 0.5% cimetidine rinses. At baseline and days 14, 21, and 28, neutrophils were harvested from prespecified gingival sulcular sites, purified, stained, and examined by trifluorochrome phagocytosis and killing microassay. The second and third studies were placebo-controlled, 9-week, three-period (each of 3 weeks' duration), longitudinal studies involving seven and nine adults with moderate periodontitis, respectively. Subjects rinsed twice a day during periods 1 and 3 with placebo and during period 2 with 0.5% cimetidine. At baseline and weekly intervals, neutrophils were harvested from prespecified periodontal pockets, purified, stained, and examined by trifluorochrome phagocytosis and killing microassay in the second study. In the third study, neutrophils were examined spectrophotometrically for superoxide production and in a luminol-enhanced chemiluminescence assay.
  
  
  RESULTS
  In the first study, the mean number of phagocytosing neutrophils was statistically significantly increased (P = 0.016) in the cimetidine group (31.1 cells/subject) versus the placebo group (13.7 cells/subject) at day 28. In addition, a statistically significant increase (P = 0.036) in bacterial killing was observed in the cimetidine rinse group; in the cimetidine group, 63.4% of bacteria in the neutrophils were killed compared to 46.2% in the placebo group. Additional data from the other two studies support these findings.
  
  
  CONCLUSIONS
  Collectively, these studies provide evidence that topical 0.5% cimetidine oral rinse enhances the antibacterial function of crevicular neutrophils.
authors.affiliation: Boston University, Goldman School of Dental Medicine, Boston, MA, USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Van Dyke
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Cutler
authors.forename: Michael
authors.initials: M
authors.lastname: Kowolik
authors.forename: Robert S
authors.initials: RS
authors.lastname: Singer
authors.forename: William
authors.initials: W
authors.lastname: Buchanan
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Biesbrock
mesh_terms: D000276:Adjuvants, Immunologic / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D002927:Cimetidine / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005883:Gingival Crevicular Fluid / Q000187:drug effects* / Q000382:microbiology; D005891:Gingivitis / Q000188:drug therapy / Q000382:microbiology; D006633:Histamine Antagonists / Q000627:therapeutic use; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009067:Mouthwashes / Q000627:therapeutic use; D009504:Neutrophils / Q000187:drug effects* / Q000276:immunology; D010518:Periodontitis / Q000188:drug therapy / Q000382:microbiology; D013481:Superoxides / Q000032:analysis
chemical_list: D000276:Adjuvants, Immunologic; D006633:Histamine Antagonists; D009067:Mouthwashes; D013481:Superoxides; D002927:Cimetidine