RESUMO
BACKGROUND AND OBJECTIVE: Recent evidence suggests that the use of fluoxetine could reduce periodontal disease severity. However, the effect of fluoxetine on periodontal disease has not been tested in the context of conditioned fear stress (CFS). We hypothesized that inhibition of chronic stress by fluoxetine might decrease the levels of bone loss in periodontal disease. The aim of the present study was to analyze the effect of fluoxetine on bone loss in chronic periodontitis. MATERIAL AND METHODS: Fourteen Wistar rats were submitted to ligature-induced periodontal disease and divided into four groups (A-D). Groups A (n = 3) and B (n = 4) were not stressed, while Groups C (n = 3) and D (n = 4) were submitted to a CFS paradigm for 38 d. Daily fluoxetine (20 mg/kg) was administered to Groups B and D from day 20 to day 39, at which point the rats were submitted to an open field test and killed on day 40. Mandibles were removed for histological and immunohistochemical analyses. RESULTS: Stress was associated with a higher level of bone loss in Group C compared with Group A. Additionally, no differences in bone loss were observed among Groups A, B and D. CONCLUSION: We showed that stress is associated with the progression of bone loss in a CFS model in rats and that fluoxetine treatment reduces the bone loss.
Assuntos
Periodontite Crônica/prevenção & controle , Medo/psicologia , Fluoxetina/uso terapêutico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Estresse Psicológico/psicologia , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/psicologia , Animais , Ansiedade/psicologia , Periodontite Crônica/patologia , Periodontite Crônica/psicologia , Condicionamento Psicológico , Modelos Animais de Doenças , Progressão da Doença , Reação de Congelamento Cataléptica/fisiologia , Interleucina-1beta/análise , Interleucina-6/análise , Locomoção/efeitos dos fármacos , Masculino , Ratos , Ratos WistarRESUMO
The aim of the present study was to determine the role of chronic stress in the pathogenesis of ligature-induced periodontal disease in rats. Fifty-three Wistar rats were randomly assigned to 4 experimental groups: 1--ligature; 2--ligature + stress; 3--stress only; 4--control. After 30 days the animals were sacrificed, blood samples were collected and histological sections were made for histometric analysis. The stress parameters evaluated were weight of thymus, spleen, adrenal glands and plasma glucocorticoid levels. Analysis of adrenal glands showed statistically significant differences between stressed and non-stressed groups (one-way ANOVA, p < 0.05). Plasma glucocorticoid levels were higher in Group 3 and lower in Group 2 (81.1 nmol/I versus 62.5 nmol/l, p < 0.05). Histometric measurements from the bone crest and from the first attached fiber were taken for all groups and for Groups 1 and 2 for the sites with and without ligatures. The ligature sites always displayed higher mean values than non-ligated sites (paired sample t test, p < 0.05). No statistically significant differences were observed between Groups 1 and 2 with regard to the ligated sites. However, differences were observed between Groups 1 and 2 in histometric bone levels in the non-ligated sites (mean values of 0.81 and 0.55 mm, respectively, p < 0.05). It may be concluded that stress can have a possible role in the activation of the hypothalamus-pituitary-adrenal (HPA) axis, with different levels of glucocorticoid release.