【作者】 吴伟；

【导师】 欧晓艳；

【作者基本信息】 南昌大学 ， 口腔医学（专业学位）， 2022， 硕士

【摘要】 目的:以SD大鼠为研究对象,观察其磨牙缺失后认知功能及肠道菌群的变化。方法:选择SPF级别雄性6周龄SD大鼠32只,体重200-300g,随机分为三组:双侧组(双侧上颌磨牙拔除,n=11只)、单侧组(单侧上颌磨牙拔除,n=11只)和对照组(不拔牙组,n=10只)。大鼠适应环境后1周建立牙齿缺失模型。建模6周后进行相关训练,一周后采用条件恐惧实验(FC实验)检测各组大鼠的认知功能,通过环境记忆测试(场景性恐惧水平测试)和声音记忆测试(条件性恐惧水平测试)计算大鼠僵直时间占总观察时间的比值来量化大鼠的认知功能水平。选择拎尾法刺激大鼠应激性排便采集大鼠粪便样本进行16Sr RNA测序检测。结果:1、实验过程中三组大鼠体重无显著性差别(P>0.05)。2、声音记忆测试(条件性恐惧水平测试)结果显示,与对照组大鼠相比,双侧组大鼠的认知功能显著性下降(P<0.05),但单侧组大鼠的认知功能无显著性改变(P>0.05)。环境记忆测试(场景性恐惧水平测试)结果显示,三组大鼠间认知功能无显著性差异(P>0.05)。3、肠道菌群检测结果显示:α多样性指数分析显示三组间没有显著差异(p>0.05);β多样性指数分析显示三组大鼠组间肠道菌群存在差异。与对照组相比,单、双侧组中普雷沃氏菌属相对丰度显著性减少(P<0.05),而拟杆菌属相对丰度显著性增加(P<0.05);与双侧组对比,单侧组毛螺菌属等相对丰度显著性增加(P<0.05);与对照、单侧组对比,双侧组中韦荣氏球菌属等相对丰度比例显著性增加(P<0.05)。结论:双侧磨牙缺失可引起大鼠认知功能下降,单双侧磨牙缺失均会发生肠道菌群变化,大鼠磨牙缺失后认知功能下降与肠道菌群变化可能有一定关联。更多还原

【Abstract】 Objective:This study aims to observe the changes of cognitive function and microbiota in SD rats after molar loss.Methods:Thirty-two SPF 6-week-old male SD rats,weighing 200-300 g,were randomly divided into three groups: bilateral group(bilateral maxillary molars extraction,n=11),unilateral group(unilateral maxillary molars extraction,n=11)and control group(n=10).The tooth loss model was established after the rats were adapted for 1w,and the rats were treated according to the group conditions.Six weeks after the modeling,the rats were trained by FC experimental fear learning,and the cognitive function of each group was detected by FC experiment one week later.After detection,feces samples were collected for 16 Sr RNA sequencing.Results:1.During the experiment,there was no significant difference in body weight among the three groups(P > 0.05).2.The results of sound memory test(conditioned fear level test)showed that compared with the control group,the cognitive function of the rats in the bilateral group was significantly decreased(P < 0.05),but the cognitive function of the rats in the unilateral group was not significantly changed(P > 0.05).Environmental memory test(situational fear level test)showed that there was no significant difference in cognitive function among the three groups(P > 0.05).3.Intestinal microflora test results showed that α diversity index analysis showed no significant difference among the three groups(P > 0.05);Compared with the control group,the relative abundance of Prevotella was significantly decreased(P< 0.05),while the relative abundance of Bacteroides was significantly increased(P <0.05).Compared with bilateral groups,the equal relative abundance of Spironella in unilateral group was significantly increased(P < 0.05);Compared with the control group and unilateral group,the proportion of equal relative abundance of Venococcus in bilateral group was significantly increased(P < 0.05).Conclusion:Bilateral molar loss can cause cognitive decline in rats,and changes in gut microbiota occur in both unilateral and bilateral molar loss groups.There may be a certain correlation between cognitive decline and changes in gut microbiota after molar loss in rats.更多还原