关键词: 尼古丁, 牙周组织, 疾病模型, 动物

Abstract: To investigate the effects of stress associated with nicotine on experimental periodontal breakdown of ligature-induced periodontitis in rats. Methods Forty male Wistar rats with the neck of left maxillary second molar ligated by nylon were used.The animals were randomly divided into four groups: Ni group,0.7 mg of nicotine•kg^-1•d^-1 (intraperitoneal); S group,stress (immobilization-12 h•d^-1); Ni+S group,stress (immobilization-12 h•d^-1) associated with an intraperitoneal injection of 0.7 mg of nicotine•kg^-1•d^-1; C group：saline solution. Two rats of each group were sacrificed at the day of 2,4,6,8,10 separately and the furcation areas of the second maxillary molars were examined histologically and histometrically. Results Intergroup analysis revealed a higher bone loss rate in the animals of Ni+S group compared with the other three groups,the absorption rate of alveolar bone at the day of 6,8,10 in experimental groups were higher than that in C group (P<0.01); the absorption rate of alveolar bone at the day of 6,10 in Ni group and Ni+S group were higher than that in S group (P<0.01) and at the day of 10,it was higher in Ni+S group compared with Ni group (P<0.05); and there were significant differences at the day of 6,8,10 between Ni group and C group (P＜0.05) and at the day of 6 between Ni group and S group (P<0.01). Conclusion Stress can significantly enhance the destructive effects of nicotine on the periodontal tissue,and they have synergetic effect in the destructive process of periodontal tissue.

Key words: nicotine, periodontal tissue, disease models, animal