口腔干预措施对牙周炎大鼠颈动脉牙龈卟啉单胞菌检出量及C-反应蛋白表达的影响

目的 建立慢性牙周炎（CP）合并高脂血症（HL）的SD大鼠模型并对其进行口腔干预,检测大鼠颈动脉局部C-反应蛋白（CRP）的表达情况及牙龈卟啉单胞菌的检出量,探讨牙周炎与动脉粥样硬化的相关性。方法 SD大鼠随机分为3组,A组为对照组,B组为HL组,C组为CP+HL组。C组分为C1组（不治疗组）,C2组（基础治疗组）,C3组（拔牙组）;C2组又分为C2-1组（单纯牙周基础治疗组）,C2-2组（牙周基础治疗+米诺环素+抗生素组）;C3组又分为C3-1组（拔除患牙组）,C3-2组（拔除患牙+抗生素组）。建模开始15周后随机处死B组大鼠1只,取颈动脉分叉血管组织进行油红O染色,观察到泡沫细胞形成则HL建模成功。建模成功后进行2次口腔干预,干预结束后5周处死所有大鼠,取双侧颈动脉血管分叉处组织,分别采用免疫组织化学法检测CRP相对含量,16sRNA半定量法检测样本中的牙龈卟啉单胞菌的相对含量。结果 免疫组织化学结果显示,B、C组CRP阳性表达明显高于A组（P<0.05）,与C1组相比,C组各干预组的CRP表达均降低（P<0.05）,其中辅助抗生素组较不加抗生素组阳性表达更低（P<0.05）,C2-2组在各干预组中阳性表达最低。牙龈卟啉单胞菌检测结果显示,C1组检出量最高,明显高于A、B组（P<0.05）;C组各干预组的检出量均较C1组低（P<0.05）,C3-2组最低（P<0.05）。结论 伴HL的牙周炎大鼠不加干预任其发展,颈动脉血管中CRP的表达及牙龈卟啉单胞菌检出量都明显增加,血管病变逐渐加重。牙周基础治疗和拔牙均可有效降低颈动脉血管中CRP的表达及致病菌含量,其中牙周基础治疗对CRP表达的降低作用更明显,拔牙对降低牙周致病菌的作用更有效;基础治疗或拔牙时若辅以局部及全身抗炎药物,均可以有效提高CRP和牙周致病菌的降低作用。

Effects of oral interventions on carotid artery in rats with chronic periodontitis for the detection ofPorphyromonas gingivalis and the expression of C-reactive protein

Objective This study aimed to establish a SD rat model of chronic periodontitis (CP) merged with hyperlipidemia (HL), perform periodontal treatment, detect the expression of partial C-reactive protein (CRP) andPorphyromonas gingivalis (P. gingivalis) in the rat carotid artery, and explore the relationship between periodontitis and atherosclerosis.Methods SD rats were randomly divided into three groups: control group (A), HL group (B), and CP+HL group (C). Group C rats were divided into natural process group (C1), scaling and root planning group (C2), and tooth extraction group (C3). Group C2 rats were randomly divided into C2-1 (scaling and root planning group) and C2-2 (scaling and root planning+minocyline+systemic antibiotics group). Group C3 rats were randomly divided into C3-1 (tooth extraction group) and C3-2 (tooth extraction+systemic antibiotic group). One rat from group B was randomly selected and sacrificed after 15 weeks. Subsequently, the carotid vas-cular tissue was collected for oil red O staining. Modeling was successful when foam cell formation was observed. Periodontal treatments were conducted twice, and euthanasia was performed after the experiment. Moreover, double-carotid artery bifurcation was carried out to detect the expression of CRP andP. gingivalis. Immunohistochemical and 16sRNA semiquantitative methods were used to detect the CRP expression and the relative contents ofP. gingivalis, respectively.Results Immunohistochemical results showed that the CRP-positive expression in groups B and C was significantly higher than that in group A (P<0.05). The CRP-positive expression in other group C rats were significantly lower than that in group C1 (P<0.05). The CRP-positive expression in group C2-2 was the lowest among the groups (P<0.05). The relative quantity ofP. gingivalis in group C1 was the highest and significantly higher than that in groups A and B (P<0.05). The relative quantities ofP. gingivalis in groups C2-1, C2-2, C3-1, and C3-2 were sig-nificantly lower than that in group C1 (P<0.05), and the quantity in group C3-2 was the lowest (P<0.05).Conclusion Rats with CP associated with HL will increase the CRP expression and oral bacteria quantity on carotid artery, and lesions will gradually aggravate. Interventions, such as periodontal basic treatment and tooth extraction, could improve carotid artery lesions. The basic treatment with local and systemic anti-inflammatory drugs exerts the most satisfactory effect on local CRP expression. Tooth extraction with antibiotics is an effective method on reducing oral bacteria in carotid artery. Periodontal basic treatment associated with local and systemic antiflammatory drugs can obviously improve the effect.