發(fā)布時間：2018-06-01 07:44

  本文選題：TLR4 + 大腸桿菌內(nèi)毒素　； 參考：《山東農(nóng)業(yè)大學(xué)》2015年碩士論文

【摘要】：家兔的腹瀉病尤其是以大腸桿菌引起的4~8周齡仔兔的腹瀉,嚴重危害了養(yǎng)兔業(yè)的發(fā)展。該病發(fā)病率、死亡率高,損失大,治愈率低的特點,引起了世界各國養(yǎng)兔者的普遍關(guān)注。大腸桿菌的致病性主要取決于其血清型,內(nèi)毒素和吸附性三個因素。大腸桿菌(Escherichia coli,E.coli)存在許多可以使人或動物致病的血清型,即使處于同一疫區(qū)的血清型也存在不同之處;大腸桿菌的內(nèi)毒素是存在于大腸桿菌外膜中的脂多糖,是主要的致病因素;菌毛是與大腸桿菌吸附性密切相關(guān)的毒力因子,是大腸桿菌侵入機體的前提條件。大腸桿菌在病兔體內(nèi)裂解后釋放出的脂多糖,被Toll樣受體家族中的TLR4識別并結(jié)合,通過以TLR4/NF-κB為主的一系列信號通路,促進各種炎癥因子的釋放,如白介素(inter-leukin,IL)-1B、IL-6、IL-8、腫瘤壞死因子(tumor necrosis factor,TNF)-A,在抗大腸桿菌感染的炎癥過程中起到重要作用。本實驗利用免疫組化的方法對不同發(fā)病時期病兔實質(zhì)器官中TLR4進行定位定量的分析,從而比較出不同器官,不同發(fā)病時期TLR4的分布規(guī)律以及各實質(zhì)器官對大腸桿菌敏感性的高低。各實質(zhì)器官中TLR4表達量的高低可以從側(cè)面說明各實質(zhì)器官在抗感染過程中產(chǎn)生的炎癥因子的多少、重要性的大小以及自身的感染程度。本實驗的研究為仔兔的大腸桿菌病提供了一定的理論依據(jù)。心臟中TLR4的表達分布于心肌纖維中;肝臟中TLR4的表達分布在肝細胞、庫普弗細胞、內(nèi)皮細胞,但膽管上皮細胞或其它細胞的細胞質(zhì)和細胞膜中也可見TLR4的表達;脾臟中TLR4的表達主要分布在白髓中的淋巴小結(jié)和動脈周圍淋巴組織鞘,在小梁處也可見到受體表達;肺臟中TLR4的表達主要分布于肺泡管、肺泡周圍,但也有少量分布于細支氣管黏膜處;腎臟中TLR4的表達主要分布于腎小管周圍的毛細血管、腎小管上皮,腎小球中也有表達。無論是健康動物還是發(fā)病動物,心、肝、脾、肺、腎中都有TLR4的表達,但是其表達量的高低水平不同;脾、腎中TLR4的表達量明顯高于心、肺、肝中TLR4表達量。而且處于同一發(fā)病階段的不同動物由于存在自身差異,導(dǎo)致其機體內(nèi)TLR4的表達量也略有不同。在不同的發(fā)病階段,不同的實質(zhì)器官在抗感染的過程中起到了極其重要的作用。在發(fā)病第1天,腎、肝、肺中TLR4的表達量達到各自的峰值,在機體抵抗大腸桿菌入侵時起重要作用;發(fā)病第3天,脾中TLR4的表達量達到其峰值,發(fā)揮其重要作用;發(fā)病第5天,心中TLR4的表達量達到其峰值。心中TLR4的表達量,第5天大腸桿菌感染組與正常對照組及第1、3、7天大腸桿菌感染組存在顯著性差異(P0.05);肝中TLR4的表達量,第1天大腸桿菌感染組與正常對照組及第3、5、7天大腸桿菌感染組差異顯著(P0.05);脾中TLR4的表達量,第3天大腸桿菌感染組與正常對照組及第1、5、7天大腸桿菌感染組差異顯著(P0.05);肺中TLR4的表達量,第1天大腸桿菌感染組與正常對照組及第3、5、7天大腸桿菌感染組差異顯著(P0.05);腎中TLR4的表達量,第1、5天大腸桿菌感染組與正常對照組及第3、7天大腸桿菌感染組存在顯著性差異(P0.05)。因為心、肝、脾、肺、腎本身所存在的TLR4受體的數(shù)量不一,所以在同一發(fā)病時期中,各實質(zhì)器官中TLR4受體的表達量之間也存在差異。根據(jù)各實質(zhì)器官中TLR4表達量的峰值以及達到峰值的發(fā)病時期,可以推算出各實質(zhì)器官對大腸桿菌侵入的敏感程度:腎肝肺脾心。
[Abstract]:Diarrhea in rabbits, especially the diarrhea caused by Escherichia coli, caused by diarrhea in 4~8 weeks old rabbits, seriously endangers the development of rabbit industry. The disease incidence, high mortality, high loss and low cure rate have caused widespread concern in the world of rabbits. The main pathogenic factors of Escherichia coli depend on the three causes of its serotype, endotoxin and adsorbability. Escherichia coli (E.coli) has many serotypes that can cause human or animal disease, even in the serotypes in the same epidemic area. The endotoxin in Escherichia coli is the lipopolysaccharide in the outer membrane of the Escherichia coli, the main cause of the disease, and the pilus is closely related to the adsorption of Escherichia coli. The force factor is the precondition for the Escherichia coli invading the body. The lipopolysaccharide released by the Escherichia coli after the lysis of the sick rabbit is identified and combined by TLR4 in the Toll like receptor family. It promotes the release of various inflammatory factors through a series of signaling pathways dominated by TLR4/NF- kappa B, such as inter-leukin (IL) -1B, IL-6, IL-8, and tumor necrosis. Tumor necrosis factor (TNF) -A plays an important role in the inflammatory process of Escherichia coli infection. This experiment uses immunohistochemical method to locate and quantify the TLR4 in the parenchyma organs of rabbits at different onset times, thus comparing the distribution of different organs, the distribution of TLR4 in different onset periods and the major organs to large organs. The high or low sensitivity of Enterobacteriaceae. The level of TLR4 expression in the various parenchyma organs can be described from the side to explain the number of inflammatory factors, the magnitude of importance and the degree of their own infection. This study provides a theoretical basis for the colibacillosis in the rabbit. The table of TLR4 in the heart. The expression of TLR4 in the liver is distributed in hepatocytes, Kupffer cells, and endothelial cells, but the expression of TLR4 in the cytoplasm and membrane of the bile duct epithelial cells or other cells is also visible; the expression of TLR4 in the spleen is mainly distributed in the lymph nodes in the white pulp and the peri arterial lymphatic sheath, and is also visible on the trabeculae. The expression of TLR4 in the lung is mainly distributed in the alveolar duct and around the alveoli, but also in the bronchioles. The expression of TLR4 in the kidney is mainly distributed in the capillaries around the renal tubules, in the renal tubules and in the glomeruli, both in the healthy and in the animals, in the heart, in the liver, in the spleen, in lung, and in the kidney. The expression of TLR4 is different, but the expression of TLR4 in the spleen and kidney is significantly higher than the expression of TLR4 in the heart, lung and liver. And the different animals in the same stage of the disease have a slight difference in the expression of TLR4 in the body. In the first day of disease, the expression of TLR4 in the kidney, liver and lung reached its peak value and played an important role in the body's resistance to the invasion of Escherichia coli. The expression of TLR4 in the spleen reached its peak and played an important role in the spleen for third days, and the expression of TLR4 in the heart reached its peak value for fifth days. Heart TLR 4 of the expression amount, fifth days of colibacilli infection group and normal control group and 1,3,7 day infection group of Escherichia coli (P0.05), the expression of TLR4 in the liver, first days of Escherichia coli infection group and normal control group and 3,5,7 day Escherichia coli infection group significant difference (P0.05), the expression of TLR4 in the spleen, third days of Escherichia coli infection group The difference between the normal control group and the 1,5,7 day colibacilli infection group was significant (P0.05), the expression of TLR4 in the lung, the first day colibacilli infection group and the normal control group and the 3,5,7 day colibacilli infection group were significantly different (P0.05), the expression of TLR4 in the kidney, the Escherichia coli infection group and the normal control group, and the infection of the Escherichia coli day 3,7 day on day 3,7. There is a significant difference in the group (P0.05). Because the number of TLR4 receptors in the heart, the liver, the spleen, the lung and the kidney itself is different, so there is also a difference in the expression of the TLR4 receptors in the parenchymal organs during the same period. Organ sensitivity to E. coli invasion: kidney, liver, lung, spleen and heart.
【學(xué)位授予單位】：山東農(nóng)業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：S858.291

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相關(guān)期刊論文 前1條

1 梁瑩;黃柏抑菌效果的實驗研究[J];現(xiàn)代醫(yī)藥衛(wèi)生;2005年20期

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本文編號：1963416