大肠埃希菌脂多糖对高脂饮食动物血脂及炎性反应的影响

目的研究大肠埃希菌脂多糖对高脂饮食兔血脂和炎性反应的影响。方法给含0．5％胆固醇的饲料，3周后，分别在第4、8、12周采用耳动脉内、颈部、腹股沟处肌肉注射大肠埃希菌脂多糖（LPS），并设立正常组和单纯高脂组。16周后观察兔的一般状态，取血清检查血脂六项、C-反应蛋白和TNF—α，取耳动脉、颈动脉、主动脉弓、胸主动脉、腹主动脉、髂动脉、肝脏，放置4％多聚甲醛中过夜，常规行HE染色，检查血管病变和相关脏器病变情况。结果单纯高脂组血清中胆固醇和LDL-C较正常组增加，复合模型组动物血清中胆固醇和LDL-C均明显高于单纯高脂组，单纯高脂组TNF-α较正常组高，复合模型组TNF-α比单纯高脂组高。病理显示主动脉弓变化明显，复合模型组内膜斑块弥漫，而单纯高脂组内膜只出现单个小斑块，单纯高脂组和复合模型组心脏病变区别不大，均见轻度水肿和小脂肪滴；单纯模型组肝脏细胞轻度水肿，而复合模型组肝脏脂肪滴明显。结论大肠埃希菌脂多糖加重了内膜斑块的形成，加剧了血脂代谢的紊乱和炎性反应。

Influences of lipopolysaccharide on the inflammation and lipid metabolism in rabbits induced by high cholesterol diet

Objective To study the influences of lipepolysaccharide on inflammation and lipid metabolism in rabbits induced by high cholesterol diet. Methods Rabbits were randomized to three groups. Complex model group were fed with feed containing 0.5 % cholesterol for 3 weeks. At the fourth, eighth and twelfth weeks, rabbits were given injection of lipopelysaccharide（ 1 μg） at auricular artery, cervical part（ i. m. ） and fold inguen（ i. m. ）, respectively. Normal group were fed with normal diet, while High cholesterol group were fed with feed confaining 0.5 % cholesterol only. After 16 weeks, vascular tissues were analyzed using morphometric and histological methods, and the sera were checked for cholesterol, LDL-C, C-reaction protein and tumor necrosis factor-α （TNF-α） . Results The cholesterol and LDL-C of High cholesterol group were increased, compared to those of normal group. The cholesterol and LDL-C of Complex medel group were obviously higher than those of High cholesterol group. The TNF-α of High cholesterol group were higher than that of noamal group, while the TNF-α of Complex model group were higher than that of High cholesterol group. Pathological results showed obvious changes in aortic arch. In Comlex model group the endangium plaque were widespread, while in that of High cholesterol group there was only single small plaque. The pathological heart changes of both High cholesterol group and Complex model group weren＇t obvious, with mild oedema and small fat drops. The liver ceils of High cholesterol group showed mild oedema, while fat drops in the liver of Complex model group were more typical. Conclusion LPS intensifies the formation of vascular plaques and aggravates the lipometabolic disorder and inflammation.