釉基质衍生物对牙周炎症组织中凋亡发生的影响

目的：探讨釉基质衍生物（EMD）对牙龈卟啉单胞菌脂多糖（Pg—LPS）龈沟内注射形成的牙周炎症组织中细胞凋亡的影响。方法：隔日向SpragueDawley大鼠双侧上颌第一及第二磨牙间腭侧龈沟内注射Pg—LPS2wk建立牙周炎模型；牙周炎形成后，龈沟内注射EMD或磷酸盐缓冲液；截取上颌骨标本，行HE染色观察牙周组织破坏情况，TUNEL染色观察牙周组织中细胞凋亡，免疫组织化学染色观察凋亡酶caspase--3和波形蛋白的表达。结果：在大鼠龈沟内注射Pg—LPS后，牙周组织形成明显的炎症和附着丧失；TUNEL染色显示EMD可以抑制Pg—LPS所致牙周组织中的细胞凋亡；免疫组织化学染色显示EMD降低凋亡酶caspase--3的表达，并且促进牙周组织中波形蛋白的表达。结论：EMD可以抑制Pg—LPS所致牙周组织中的细胞凋亡，从而促进牙周组织再生。

Effects of Enamel Matrix Derivatives on Apoptosis in Periodontal Inflammatory Tissue.

Objective： To evaluate the effects of enamel matrix derivatives （EMD） on apoptosis in inflammatory periodontal tissue by injection of porphyromonas gingivalis lipopolysaccharide （Pg--LPS） via gingivals sulcus. Methods： Periodontitis model was established by Pg--LPS gingival sulcus injection between 1st and 2nd upper mo- lars in Sprague Dawley rats, and then EMD or phosphate buffer solution was injected into gingival sulcus. Maxilla was segmented; periodontal tissue loss was evaluated by hematoxylin and eosin stain~ terminal--deoxynucleotidyl transferase mediated nick end labeling（TUNEL）was utilized to assess apoptosis in periodontal tissue; immunohisto- logical staining of caspase--3 and vimentin was conducted to investigate effect of EMD on apoptotic gene expression and fiber formation. Results： Periodontal inflammation and attachment loss was observed in LPS injected periodontal tissue. EMD inhibited LPS-- induced apoptosis in periodontal tissue. EMD decreased caspase-- 3 expression and promoted vimentin expression in periodontal tissue. Conclusion： EMD could suppress Pg--LPS induced apoptosis in periodontium, which may be one mechanism for its periodontal regeneration potential.