| [Objective]Streptococcus sanguis (Ss) is one of the most popular bacteria in the oral cavity, which associates with various diseases. Porphyromonas gingivalis(Pg) is one kind of anaerobic gram-negative bacteria associated with the chronic periodontitis. Yet, their roles in platelet adhesion and congregation are poorly understood, especially in the dynamic processes in the human body. The purpose of this experiment is to use the static aggregometer and parallel plate flow chamber (vitro dynamic platelet thrombus model on the parallel plate flow chamber system) to observe the aggregation of the platelets promoted by Ss/Pg and the influence on the platelets aggregation when Ss and Pg combined together, meanwhile use the Listerine antiseptic mouthrinse and Xipayi mouthrinse to inhibit the affection of the bacterial. The aim of this study is to discusses the mechanism of these two oral bacteria on the coronary heart disease and observe the clinical value of antimicrobial drugs.[Methods] 1. Platelet aggregation assay. The same amount of Ss, Pg, Ss+Pg mixed solution were added to the same amount of PRP respectively; PRP with adrenaline as the positive control, and with PBS as the negative control. Aggregation was measured using a recording platelet aggregometer.2. The affection of the two antimicrobial drugs on the bacterial. Ss, Pg, Ss+Pg mixed solution were pretreated with Listerine antiseptic mouthrinse and Xipayi mouthrinse respectively. The same amount of the solutions above were added to the PRP respectively. The inhibition of aggregation was measured using a recording platelet aggregometer.3. The flow chamber system. Platelets were labeled with an anti-CD41 fluorescence monoclonal antibody, passed through a parallel plate flow chamber with Ss, Pg or a biofilm of Ss and Pg coated with saliva. Platelets'adhesion to the chamber was consistently observed under the fluorescence microscope for 15 min. while platelets' aggregation was also studied. Flow chamber with adrenaline served as the positive control, and PBS only as the negative control.[Result]1. Platelet aggregation assay. Ss and Pg were able to induce the platelets aggregation, with mean (±S.E.) aggregation rate of 77.67±7.37%,79.33±9.87%, and mean (±S.E.) lag times of 6.73±1.47min,1.56±0.21min. The lag times of Ss was significantly higher than Pg (P＜0.05); the aggregation rate of Ss+Pg is 51.33±12.86%, significantly lower than Ss/Pg (P<0.05), but the lag times of Ss+Pg has no statistical significance with Ss/Pg (P>0.05).2. The affection of the two antimicrobial drugs on the bacterial. When Ss, Pg, Ss+ Pg mixed solution were pretreated with Listerine antiseptic mouthrinse for 3min and Xipayi mouthrinse for 10min, there was no significant platelet aggregation(P<0.01).3. The flow chamber system. In the negative control, no adhesion or congregation of the platelets was observed; Platelets adhered to Ss and Pg within 3min, respectively, and congregation was observed within 3 min, reached the plateau at 5-15 min, when compared with the negative control(P<0.05). Under the condition of the Ss-Pg-saliva biofilm, platelets'adhesion to the biofilm was significantly reduced at 5-15 min, when compared with individual Ss or Pg (P<0.05).[Conclusion]Either in the static or the dynamic flow system, platelets could adhere to Ss or Pg respectively, but when Ss mixed with Pg, the aggregation rate was significantly reduced. The bacterial can't promote the platelets to aggregate after being treated with Listerine antiseptic mouthrinse and Xipayi mouthrinse. Using the static aggregometer and the imitating circulation system can help us study the dynamic changes in thrombus promoted by Ss or Pg more in-depth, which provided the novel evidences in elucidating pathogenesis of Ss and Pg.
|
PDF Full Text Request