中文摘要：

为探讨TLR2在乳房链球菌（Streptococcus uberis）感染小鼠乳腺后对血浆中抗氧化能力及细胞因子产生的影响,本研究以B6小鼠TLR2＋/＋（野生型）和TLR2-/-（TLR2敲除）B6小鼠为研究对象,在小鼠分娩72 h时,乳腺灌注乳房链球菌（设生理盐水灌注对照）,24 h后采集血液并制备血浆。实验结果表明：TLR2＋/＋小鼠血浆中总抗氧化能力（T-AOC）显著高于TLR2-/-小鼠,乳房灌注乳房链球菌后TLR2＋/＋及TLR2-/-小鼠血浆中T-AOC水平均显著降低,同对照组相比差异显著（P〈0.05）,且TLR2＋/＋中也显著高于TLR2-/-型;超氧化物歧化酶（SOD）活力在TLR2-/-小鼠中无变化,而在野生小鼠中显著降低,丙二醛（MDA）含量在两种小鼠中均显著升高,野生型小鼠中含量低于敲除小鼠（P〈0.05）;TLR2-/-小鼠在乳房链球菌感染后血浆中肿瘤坏死因子-α（TNF-α）分泌显著增加（P〈0.05）;野生型小鼠在感染后白细胞介素-6（IL-6）分泌显著增加（P〈0.05）。研究表明,TLR2参与了乳房链球菌诱发乳腺局部炎症后的机体整体水平的抗氧化能力及细胞因子分泌的变化,但不是唯一因素。

英文摘要：

In order to investigate the role of TLR2 in total anti-oxidant capacity（ T-AOC） and the production of cytokines in serum from mice infected by Streptococcus uberis（ S. uberis）,the wild type B6（ TLR2＋/＋） mice and the TLR2-deficient（ TLR2-/-） mice were utilized to perform our experiment,at the 72 ndh after parturition. Mammary glands of female mice in experimental groups were infused with S. uberis,while control groups were infused with saline. Blood samples were aseptically collected at the 24 thh post-infusion by euthanatizing the mice to produce serum. The results presented that the level of T-AOC in serum from TLR2-/-mice was lower than TLR2＋/＋mice. After the infection of S. uberis,the level of T-AOC significantly decreased in both TLR2＋/＋and TLR2-/-mice compared with control groups（ P〈0. 05）. The activity of SOD in TLR2-/-mice showed no changes,however,it significantly reduced in TLR2＋/＋mice. The production of MDA obviously increased in these two kinds of mice,and the increasement in TLR2＋/＋mice was lower than TLR2-/-mice（ P〈0. 05）. The secretion of TNF-αin TLR2-/-mice and IL-6 in TLR2＋/＋mice elevated after infection（ P〈0. 05）. These results indicated that TLR2 participated in mediating the level of T-AOC and the secretion of cytokines in S. uberis-induced mastitis,but it was not the unique factor.