中文摘要：

[目的]本试验通过卡介菌多糖核酸对内毒素诱发的实验性山羊乳腺炎乳腺组织的保护研究,探讨灌注免疫增强剂BCG-PSN对乳腺组织的影响,研究调动乳腺自身的防御功能,以防治乳腺炎的发生.[方法]选取泌乳初期健康睢宁白山羊6只,左乳区经过乳头管灌注卡介菌多糖核酸5 ml,右乳区灌入5 ml注射用生理盐水作为对照,连灌6 d.第7天按50 μg·kg^-1体重分别向左、右乳区灌注大肠杆菌内毒素.灌注前及灌注后0、1、2、3、4、5、6、7、8、9、24 h观察山羊整体及乳房局部变化.灌注24 h后,处死动物,取乳腺组织,部分Bouin氏液固定、部分液氮保存.[结果]临床症状及病理切片观察均显示,山羊表现典型的急性乳腺炎症状.与灌注生理盐水对照相比,乳腺灌注卡介菌多糖核酸能显著降低乳腺组织中部分炎症相关因子的含量及其基因表达水平.其中N-乙酰-β-D-氨基葡萄糖苷酶（NAGase）、髓过氧化物酶（MPO）、碱性磷酸酶（AKP）、诱导型一氧化氮合成酶（iNOS）活性显著降低（P＜0.05）;IL-1β、TNF-α的含量及其mRNA表达水平均显著降低（P＜0.05）,IL-6的含量显著降低（P＜0.05）,其mRNA表达水平有所降低但差异不显著（P＞0.05）.[结论]灌注卡介菌多糖核酸可以抑制乳腺组织内IL-1β、TNF-α等炎性细胞因子及和炎症相关酶的过度释放、减轻炎症因子对乳腺上皮细胞的损伤,对内毒素诱发的山羊实验性乳腺炎有较强的保护作用.

英文摘要：

[Objective]The study looked at the therapeutic method of mastitisand the protection of polysaccharide nucleic acid fraction Bacillus Guerin in goat mammary tissue. The mastitis was induced by endotoxin. [Method] Six healthy Suining white goats at early stages of lactation were infused with a polysaccharide nucleic acid fraction of Bacillus Calmette Guerin （BCG-PSN） （5ml） in the left quarters. Physiological saline （5ml） was infused in the control contralateral quarters. The administration of BCG-PSN was carded out for six consecutive days. On the seventh day, the mammary quarters （both right and left） of the six goats were infused with Escherichia coli endotoxin （LPS） （50μg/bwt）. At varying intervals of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 24h before and after infusion inflammation was recorded. After 24h, the animals were slaughtered and mammary tissue was collected. A section was fixed for histopathological evaluations and the remaining tissue was stored at -70℃, [Result] Clinical and histopathological examinations indicated that infusion of endotoxins induced acute mastitis in both quarters. The results showed that infusion of BCG-PSN significantly reduced activity of N-acetyl-β-D-glucosaminidase （NAGase）, Myeloperoxidase （MPO）, alkaline phosphatase （AKP）, nitric oxide synthase （iNOS） and the concentration of tumor necrosis factor-or （TNF-α）, interleukin-1β （IL-1β）, and interleukin-6 （P〈0.05）. There was a general reduction in the levels of mRNA cytokine expression （P〈0.05）. [Conclusion] These findings suggest that BCG-PSN inhibits release of inflammatory factors that cause damage to mammary epithelial cells during mastitis infections in goats.