硫化氢在正畸牙牙周组织改建中作用的大鼠实验研究

目的 观察硫化氢（hydrogen sulfide,H2S）对大鼠正畸牙牙周组织改建的影响,并与一氧化氮（nitric oxide,NO）对比,初步探讨其在改建过程中的作用及机制.方法 利用45只雄性Sprague-Dawley（SD）大鼠建立正畸牙移动模型,动物随机分为三组：阴性对照组（A组）局部注射无菌磷酸缓冲盐溶液（phosphate-buffered saline,PBS）;实验组（B组）局部注射40 mg/ml DL-炔丙基甘氨酸（DL-propargylglycine,PPG）;阳性对照组（C组）注射相同浓度NG-硝基精氨酸甲酯（NG-Nitro-L-arginineMethylEster,L-NAME）.于加力第7,14,21天分批处死大鼠,制作切片.应用抗酒石酸酸性磷酸酶（tartrate resistant acid phosphatase,TRAP）染色计数破骨细胞数,链霉亲和素-生物素复合物（strept avidin-biotin complex,SABC）染色检测胱硫醚-γ-裂解酶（eystathionine γ-lyase,CSE）及诱导型一氧化氮合酶（inducible nitric oxide synthases,iNOS）阳性表达的平均光密度值.结果 加力第7天,B组破骨细胞数明显少于其余两组（P＜0.01）,CSE表达量在C组中最高.加力14,21天B组破骨细胞数呈先增加后减少趋势,A、C两组则呈递减趋势;CSE和iNOS表达量均逐渐减少,但21天时CSE基本呈阴性表达,而iNOS表达量仍较高（P＜0.01）.结论 应用40 mg/ml PPG可减少正畸牙早期H2S的生成,抑制破骨细胞募集;在正畸牙移动牙周组织改建过程中,NO/iNOS与H2 S/CSE体系间可能存在负性调节作用.

Effects of hydrogen sulfide on periodontal tissue remodeling of orthodontic tooth in rats

Objective To assess the effects of H2S on periodontal tissue remodeling and possible interaction between H2S and NO in rat model of orthodontic tooth movement （OTM）.Methods The OTM models were established in three groups of 45 male Sprague-Dawley rats.The rats in the negativecontrol group （Group A） received injection of sterile phosphate-buffered saline （PBS）,and those in the treatment group （Group B） and positive control group （Group C） respectively received 40 mg/ml DL-propargylglycine （PPG） and NG-Nitro-L-arginine Methyl Ester （L-NAME）.Histochemistry and immunohistochemistry were performed respectively to exam the number of tartrate-resistant acid phosphatase（TRAP） positive osteoclast and expression of cystathionine γ-lyase （CSE） and inducible nitric oxide sythase （iNOS） in the tissue sections containing intact roots and periodontal tissues of the first molar on day 7,14 and 21 after appliance insertion.Results Group B had lest osteoclasts on day 7,compared to the other two groups（P〈0.01） while Group C showed the most expression of CSE.Increasing number of osteoclasts were observed in the first 14 days but followed with a decrease on day 21 in Group B.Osteoclast number decreased in Group A and C during the course.The expressions of both enzymes were down-regulated gradually.On day 21,CSE expression was negative whereas iNOS remained relative high expression（P〈0.01）.Conclusions Application of 40 mg/ml PPG can reduce the generation of the endogenous H2S,and prevent osteoclasts from recruiting in the early stage of OTM.There may be down-regulation effect between NO/iNOS and H2 S/CSE during orthodontic periodontal tissue remodeling.