老年牙周炎牙龈组织诱导型一氧化氮合酶分布研究

Distribution of inducible nitric oxide synthase in gingival tissues in elderly patients with periodontitis

目的 :观察慢性老年牙周炎患者牙龈组织中诱导型一氧化氮合酶 (iNOS)分布。方法 :采用免疫组织化学方法对 10例慢性老年牙周炎患者、10例慢性成人牙周炎患者、10例青少年牙周炎患者和 10例健康老年人牙龈组织中诱导型一氧化氮合酶分布进行了检测并比较研究。结果 :(1)牙周炎时牙龈组织中诱导型一氧化氮合酶主要在鳞状上皮细胞胞浆核周区颗粒状阳性表达 ,毛细血管壁内皮细胞、老化的胶原纤维及上皮下基底膜共同形成了一种乳头状轮廓样阳性表达形态 ,结缔组织和肉芽组织中各类炎症细胞也显阳性表达 ;(2 )慢性老年牙周炎组血管壁内皮细胞、结缔组织内炎症细胞、上皮乳头阳性表达例数明显低于青少年牙周炎组和慢性成人牙周炎组 (P <0 .0 5 )。血管壁内皮细胞和胶原纤维阳性表达例数低于健康老年人组 (P <0 .0 5 )。结论 :慢性老年牙周炎患者牙龈组织中诱导型一氧化氮合酶的表达明显降低 ,造成了局部一氧化氮(NO)合成减少 。

Objective: To observe the distribution of inducible nitric oxide synthase (iNOS) in gingival tissues in elderly patients with periodontitis. Methods: Gingival tissue samples were obtained during tooth extraction.The localization of positive expression of iNOS in gingival tissues in 10 patients aged 65-86 years with periodontitis was tested with immunohistochemical method and was compared with that of 10 adult patients(37-54 years old) with periodontitis, 10 juvenile patients (18-29 years old) with periodontitis and 10 healthy elders(65-81 years old),respectively. Results:iNOS expression was mainly found in epithelial cells, inflammatory cells in connective tissues, granuloma tissues, epithelial basement membrane and microvascular endothelial cells in gingiva in the 3 groups of periodontitis. The cases of positive expression of iNOS in microvascular endothelial cells and inflammatory cells in connective tissues in elderly patients with periodontitis were significantly fewer than those in juvenile patients and adult patients ( P < 0.05 ); The cases of positive expression of iNOS in microvascular endothelial cells and collagen fibrils in elderly patients with periodontitis were obviously fewer than those in healthy elders ( P < 0.05 ). Conclusion: Aging and inflammation may result in decrease of positive expression of iNOS in gingival tissues in elderly patients with periodontitis and the production of NO in gingival tissues may be reduced.