大肠杆菌对兔实质器官氧化损伤指标及脾脏中CD14分布的影响

发布时间：2018-07-05 12:32

本文选题：兔大肠杆菌病 + 实质器官　；参考：《山东农业大学》2015年硕士论文

【摘要】：大肠杆菌病是由一定血清型的致病性大肠杆菌及其毒素引发的一种肠道传染病。该病一年四季都能发生,感染各个年龄段的兔子,但主要对断乳至4月龄仔兔的威胁最大。为进一步探讨大肠杆菌对病兔实质器官的影响,本实验以人工感染的大肠杆菌仔兔为实验对象,通过对患病仔兔实质器官氧化损伤指标的检测及免疫组化法(ICH)检测不同发病时期病兔脾脏中CD14的分布情况,从一个新的角度研究致病性大肠杆菌对机体的病理损伤情况,为进一步防治大肠杆菌病提供新的临床依据。本实验将32只30~40日龄的新西兰兔平均分为对照组与发病组两组,发病组人工腹腔注射大肠杆菌原液,对照组腹腔注射等量生理盐水,分别采取两组第1、3、5、7d仔兔各实质器官(心、肝、脾、肺、肾)1 cm3液氮速冻,保存于-80℃冰箱备用,用于检测各实质器官氧化损伤指标。分别测定各器官的SOD活性,MDA及蛋白含量,分析比较发病组与对照组各指标变化以及发病组不同发病时期各指标的变化规律。另取1cm3脾脏,用生理盐水将实质器官表面冲干净后固定于40 g/L多聚甲醛中,制作石蜡切片,用于免疫组化法检测仔兔脾脏中CD14的分布情况,统计仔兔脾脏的血管,白髓,红髓,小梁CD14的阳性率,分析比较发病组与对照组CD14分布情况以及发病组不同发病时期阳性率的变化规律。病理解剖结果:病兔腹腔内存在大量纤维蛋白,有明显的臭味,肠壁外附着有大量的纤维蛋白,结肠壁有出血现象,肠内粪便呈胶冻状,肝脏和肺脏有明显的充血、出血现象,脾脏外附着有大量纤维蛋白,个别病兔肾脏出现充血现象。氧化损伤指标结果:发病兔实质器官SOD活性比对照组低,并且发病组随病情发展呈先降低后升高的趋势。肝脏在第一天SOD活性达到最低,心脏和脾脏在第三天达到最低,肺脏和肾脏在第五天达到最低。其中心脏在第三天与对照组存在极显著差异(P0.01),肝脏在第一天与对照组相比存在显著差异(P0.05),脾脏在第三天与对照组存在显著差异(P0.05),肺脏和肾脏在第五天与对照组相比存在显著差异(P0.05);蛋白含量发病组比对照组升高,发病组随病情发展呈先升高后降低趋势,其中心脏在第三天与对照组存在显著差异(P0.05),肝脏在第一天与对照组存在显著差异(P0.05),肾脏在第五天与对照组存在显著差异(P0.05);MDA值比对照组升高,发病组随病情发展呈先升高后降低的趋势。肝脏在第一天达到最高,心脏和脾脏在第三天达到最高,肺脏和肾脏在第五天达到最高。其中心脏和脾脏在第三天与对照组存在显著差异(P0.05),肺脏在第五天与对照组存在显著差异(P0.05),变化趋势与临床表现相吻合。免疫组化结果:所采取的对照组脾脏有4组CD14检测为阴性,其余12组均出现阳性;发病兔的脾脏中均检测为阳性,并且阳性结果非常明显,其中血管周围分布最多,小梁及白髓分布较多,红髓中分布较少。对脾脏中各部位CD14的阳性表达数据进行分析显示,发病组较对照组表达量升高,并随着病情发展,阳性表达率先升高后降低,在第三天和第五天的表达较高。其中白髓中的表达量在第三天比对照组显著增加(P0.05);红髓在第五天比对照组显著增加(P0.05),第三天与对照组相比存在极显著差异(P0.01);血管和小梁在第一天、第三天和第五天与对照组相比存在极显著差异(P0.01)。实验结果表明,健康仔兔人工感染大肠杆菌后,各实质器官的氧化损伤指标均受到影响,并且不同器官的最高氧化损伤程度发生在不同发病时期。肝脏在第一天、心脏和脾脏在第三天、肺脏和肾脏在第五天的氧化损伤最高。免疫组化结果表明,仔兔在发病期脾脏中CD14敏感性增强,并在第三天达到最高,与氧化损伤结果相吻合,表明仔兔大肠杆菌除了对肠道产生损伤外,对实质器官也产生了一定程度的损伤。
[Abstract]:Colibacillosis is an enteric infectious disease caused by a certain serotype of pathogenic Escherichia coli and its toxin. The disease can occur all the year round and infect rabbits of all ages, but it is the main threat to weaning to 4 month old rabbits. By detecting the oxidative damage index of the parenchyma organs of the infected rabbits and detecting the distribution of CD14 in the spleen of the sick rabbits at different onset period, the distribution of the infected rabbit's spleen was detected by the Immunochemistry method (ICH), and the damage of the pathogenic Escherichia coli to the body was studied from a new angle, so as to further prevent the colibacillosis. 32 30~40 day old New Zealand rabbits were divided into two groups in the control group and the onset group. The disease group was injected with the abdominal injection of Escherichia coli, and the control group was injected with equal amount of saline in the abdominal cavity. The 1 cm3 liquid nitrogen freezer of the two groups of 1,3,5,7d rabbits (heart, liver, spleen, lung and kidney) was taken respectively, and stored at -80 C ice. The SOD activity, MDA and protein content of each organ were measured respectively, and the changes of the indexes of the disease group and the control group and the changes of the indexes in the different onset period of the disease group were analyzed and compared. The spleen of the 1cm3 and the surface of the parenchyma organs were washed and fixed to 40 g/L after the surface of the parenchyma organs were washed with saline. Paraffin section was made to make paraffin slices, and the distribution of CD14 in the spleen of rabbit was detected by immunohistochemistry. The positive rates of blood vessels, white pulp, red pulp and trabecular CD14 in rabbit spleen were statistically analyzed. The distribution of CD14 and the change of positive rate in different onset groups of the disease group and the control group were analyzed and compared. The pathological anatomical results: the abdominal cavity of the sick rabbit There is a large amount of fibrin in a large number of fibrin, a large number of fibrin protein attached to the wall of the intestines, bleeding in the colon wall, gelatinous feces in the intestines, obvious congestion in the liver and lungs, bleeding, a large amount of fibrin attached to the spleen outside the spleen, and the phenomenon of hyperemia in the kidney of a few sick rabbits. The result of the oxidative damage index: the rabbit parenchyma The SOD activity of the organs was lower than the control group, and the onset group decreased with the development of the disease first and then increased. The liver had the lowest SOD activity on the first day, the heart and spleen reached the lowest in third days, the lungs and the kidneys reached the lowest in the first day. The heart was significantly different from the control group on the third day (P0.01), the liver was on the first day. There was significant difference in the control group (P0.05), the spleen was significantly different from the control group at third days (P0.05), the lungs and kidneys were significantly different from the control group on the fifth day (P0.05); the protein content group was higher than the control group, and the onset group increased with the development of the disease, and the heart was stored at third days with the control group. In the significant difference (P0.05), the liver was significantly different from the control group on the first day (P0.05), the kidney was significantly different from the control group at fifth days (P0.05); the MDA value was higher than the control group. The incidence of the disease was higher and then decreased with the development of the disease. The liver reached the highest on the first day, the heart and spleen reached the highest in the third day, lung and kidney. There was a significant difference between the fifth days in the fifth days. The heart and spleen were significantly different from the control group on the third day (P0.05), and there was a significant difference between the control group and the control group on the fifth day (P0.05). The change trend was consistent with the clinical manifestation. The immunization results showed that there were 4 groups of CD14 in the spleen of the control group and the other 12 groups were positive. The positive results of the rabbit's spleen were positive, and the positive results were very obvious. The distribution of the trabeculae and the white pulp were most, the distribution of the trabeculae and the white pulp were more, the distribution of the positive expression of CD14 in the spleen was higher than that of the control group, and the positive expression was first increased with the development of the disease. The expression in the third and fifth days was higher in the third and fifth days than in the control group (P0.05), the red pulp increased significantly on fifth days (P0.05), and the third day was significantly different from the control group (P0.01); the blood vessels and trabeculae were compared with the control group at the first, third and fifth days. The experimental results showed that after artificial infection of Escherichia coli in healthy rabbits, the oxidative damage indexes of all the parenchymal organs were affected, and the highest degree of oxidative damage in different organs occurred at different times. On the first day of the liver, the heart and spleen were third days, the lungs and kidneys were the most oxidative damage in the fifth day. The results of immuno histochemistry showed that the sensitivity of CD14 in the spleen increased at the onset of the onset and reached the highest in third days, which was consistent with the results of oxidative damage. It showed that the Escherichia coli had a certain degree of damage to the parenchyma in addition to the damage to the intestine.
【学位授予单位】：山东农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S858.291

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