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目的:观察腹腔注射百草枯（PQ）构建的帕金森（PD）小鼠模型的肠道时间依赖性改变，初步建立脑肠轴的联系。方法:于2019年10月，将48只小鼠随机分为染毒4周（P-4）组、染毒6周（P-6）组、染毒8周（P-8）组、对照4周（C-4）组、对照6周（C-6）组、对照8周（C-8）组，每组6只。染毒组腹腔注射15 mg/kg PQ溶液，对照组腹腔注射生理盐水（0.2 ml/20 g），每周2次。分别于初始状态（0周）及4、6、8周末次给药后，通过神经行为学测试（旷场、爬杆、悬尾及高架十字迷宫实验）评估小鼠的情绪变化和运动功能；收集小鼠1 h粪便，计算粒数及含水量评估肠道功能状态；免疫印迹实验检测小鼠中脑黑质区α突触核蛋白（α-syn）、酪氨酸羟化酶（TH），结肠闭锁小带蛋白-1 (ZO-1）、闭合蛋白（Occludin），炎症标志物分化抗原簇分子11b （CD11b）、诱导型一氧化氮合酶（iNOS）、高迁移率族蛋白B1 （HMGB1）、白细胞介素-1β（IL-1β），神经元标志物β-微管蛋白-Ⅲ（βⅢ-tubulin）、α-syn蛋白的表达水平；免疫组织化学染色检测结肠紧密连接蛋白ZO-1和Occludin表达水平；免疫荧光染色检测中脑黑质区TH表达水平及结肠神经元标志物βⅢ-tubulin和磷酸化（S129）α突触核蛋白（Ser129 α-syn）共定位。结果:与初始状态（0周）和C-8组比较，P-8组小鼠爬杆测试得分和静止时间明显增高，活动总路程、平均活动速度、开放臂进入次数百分比和1 h粪便粒数明显降低（n P<0.05）；染毒后，模型小鼠1 h粪便含水量先升高后降低，P-4组和P-6组明显高于相同时间点对照组，P-8组明显低于初始状态（n P<0.05）。与对照组（C-8组）、P-4组和P-6组比较，P-8组小鼠ZO-1、Occludin蛋白表达水平明显降低（n P<0.05）。与对照组比较，P-4组小鼠早期炎症标志物CD11b和IL-1β表达水平明显升高（n P<0.05）；与对照组和P-4组比较，P-6组和P-8组小鼠CD11b、iNOS、HMGB1和IL-1β表达水平明显升高（n P<0.05）。与对照组和P-4组比较，P-8组小鼠结肠βⅢ-tubulin表达水平明显降低，α-syn和Ser129 α-syn表达水平明显升高（n P<0.05）；模型小鼠结肠Ser129 α-syn与βⅢ-tubulin表达水平呈负相关（n rn s=-0.914 9，95%n CI:-0.977 1~-0.708 5，n P<0.001）；Ser129 α-syn和βⅢ-tubulin在结肠肌间神经丛区域共定位随染毒时间逐渐增多。与对照组、P-4组和P-6组比较，P-8组小鼠中脑黑质区TH表达水平明显降低，α-syn和Ser129 α-syn表达水平明显增加（n P<0.05）；模型小鼠中脑黑质区Ser129 α-syn与TH相对表达水平呈负相关（n rs=-0.971 6, 95%n CI：-0.992 5~ -0.895 3，n P<0.001）。n 结论:通过腹腔注射PQ成功构建PD小鼠模型，且模型小鼠肠道功能呈时间依赖性降低，初步确定异常聚集的α-syn可能是沟通脑肠轴的重要物质之一。“,”Objective:To observe the intestinal time-dependent changes in Parkinson\'s disease (PD) mouse model constructed by intraperitoneal injection of paraquat (PQ) and to establish the brain-gut axis connection initially.Methods:In October 2019, 48 mice were randomly divided into treated group and control groups: treated 4-week (P-4) group, treated 6-week (P-6) group, treated 8-week (P-8) group, control 4-week (C-4) group, control 6-week (C-6) group, and control 8-week (C-8) group. The treated group was injected with 15 mg/kg PQ solution and the control group was injected with 0.9% saline (0.2 ml/20 g) by intraperitoneal injection twice a week. After the initial state (0 weeks) and the treatment at the end of 4, 6 and 8 weeks, the mood changes and motor functions of mice were assessed by neurobehavioral tests (open field test, pole climbing test, tail suspension test and elevated plus maze test) . And the number of fecal pellets for 1 h and water content were calculated to assess the functional status of the gastrointestinal tract. Western blotting experiments were performed to detect the expression levels of α-synuclein (α-syn) and tyrosine hydroxylase (TH) in the nigrostriatal region of the mouse brain, the tight junction markers zonula occludens-1 (ZO-1) and Occludin, the inflammatory markers of integrin αM subunit (CD11b) , inducible nitric oxide synthase (iNOS) , high mobility group box 1 (HMGB1) , interleukin-1β (IL-1β) , and the neuronal markers βⅢ-tubulin and α-syn protein in the colon.Immunohistochemical staining was performed to detect the expression levels of colonic tight junction proteins ZO-1 and Occludin. Immunofluorescence staining was performed to detect the expression levels of TH in the substantia nigra region of the midbrain, and the co-localization of colonic intestine neuronal marker (βⅢ-tubulin) and Ser129 α-syn in the colonic.Results:Compared with the initial state (0 weeks) and C-8 group, mice in the P-8 group had significantly higher pole climbing test scores and resting time, and significantly lower total active distance, mean active speed, percentage of open arm entry and 1 h fecal instances (n P<0.05) . After poisoning, the 1 h fecal water content of model mice first increased and then decreased, the P-4 and P-6 groups were significantly higher than the simultaneous point control group, and the P-8 groups were significantly lower than the initial state (n P<0.05) . Compared with control, P-4 and P-6 groups, the expression levels of ZO-1 and Occludin in the P-8 group were significantly decreased (n P<0.05) . Compared with control group, the expression levels of CD11b and IL-1β in the P-4 group were significantly increased (n P<0.05) . Compared with control and P-4 group, the expression levels of CD11b, iNOS, HMGB1 and IL-1β in the P-6 and P-8 groups were significantly increased (n P<0.05) . Compared with the control and P-4 groups, the expression levels of βⅢ-tubulin in the colon of mice in the P-8 group were significantly decreased, and the expression levels of α-syn and Ser129 α-syn were significantly increased (n P<0.05) . The expression level of Ser129 α-syn in the colon of model mice was negatively correlated with the expression level of βⅢ-tubulin (n rs=-0.9149, 95%n CI: -0.9771--0.7085, n P<0.001) . Ser129 α-syn and βⅢ-tubulin co-localization in the colonic intermuscular plexus region increased gradually with the time of exposure. Compared with the control, P-4 and P-6 groups, the expression level of TH in the nigrostriatal region of the brain was significantly decreased, and the expression levels of α-syn and Ser129 α-syn were significantly increased in the P-8 group (n P<0.05) . Correlation analysis showed that the relative expression level of Ser129 α-syn in the nigrostriatal region of the brain was negatively correlated with the expression level of TH in the model mice (n rs=-0.9716, 95% n CI: -0.9925--0.8953, n P<0.001) .n Conclusion:The PD mouse model is successfully established by PQ, and the intestinal function of the model mice is reduced in a time-dependent manner. And on this basis, it is preliminary determined that the abnormal aggregation of α-syn may be an important substance connecting the brain-gut axis.