高脂饮食诱导的肥胖和肥胖抵抗大鼠胰岛素敏感性和血脂谱改变

Changes of insulin sensitivity and lipid profile in obese rats and obesity resistant rats under high fat diet inducement

目的:探讨高脂饮食诱导下大鼠各肥胖评定指标、胰岛素敏感性及血脂谱的变化,为指导人们调整不合理饮食结构提供依据。方法:20只6周龄雌性SD大鼠分为2组,正常对照组(NS)7只,高脂饮食诱导组(HS)13只,分别给予基础饲料和高脂饲料17周。根据高脂组中大鼠体重差异分为肥胖组和肥胖抵抗组。比较各组大鼠肥胖评定指标、胰岛素敏感性及血脂谱的差异。结果:高脂饮食组大鼠与正常对照组大鼠的体重、体长及Lee指数(肥胖评定指标)比较,均无统计学差异(P>0.05);与正常对照组相比,高脂饮食组大鼠空腹胰岛素显著升高(P<0.05),空腹血糖及IR指数也显著升高(P<0.01)。在血脂谱方面,高脂饮食组与正常对照组的TG、HDL无统计学差异;但是,与正常对照组相比,高脂饮食组的TC显著上升(P<0.05),LDL也显著上升(P<0.01)。肥胖组与肥胖抵抗组只有体重存在统计学差异(P<0.05),其他指标(体长、Lee指数、空腹血糖、空腹胰岛素、IR指数及血脂)均无统计学差异(P>0.05)。但是,与正常对照组相比,肥胖抵抗组的空腹血糖、空腹胰岛素、IR指数和LDL也显著升高(P<0.05)。结论:长期高脂饮食虽然有可能不使体重产生明显增加,表现出肥胖抵抗,但仍会发生明显的胰岛素抵抗和血脂代谢的紊乱。

Objective： To explore the changes of insulin sensitivity and lipid profile in obese rats and obesity resistant rats induced by high fat diet and provide theoretical basis for the adjustment of people ＇s irrational diet and reduce the incidence of some diseases. Methods： Twenty female SD rats （aged six weeks） were randomly divided into two groups, seven in normal control group （NS）, thirteen in high fat diet induced group （HS） . The rats were fed with basic diet and high diet for 17 weeks, seperately. Then the HS rats were divided into high fat diet induced obese （ HS - OB） rats and high fat diet induced obesity resistant （ HS - OR） rats according to their weight. The differences of obese evaluation index, insulin sensitivity and lipid profile between each group were compared. Results： There no significant difference in weight, length of body, and Lee index （obese evaluation index） between rats in high fat diet induced group and nor- mal control group （P 〉 0. 05） . The level of insulin in high fat diet induced group was significantly higher than that of normal control group （P 〈 0. 05）, so were the fasting blood glucose and insulin resistance （IR） index （P 〈 0. 01 ） . With regards to lipid profile, there were no significant differences in TG and HDL between rats in high fat diet induced group and normal control group （P 〉 0. 05 ） . While the level of TC in high fat diet induced group was significantly higher than that of normal control group （P 〈0. 05）, so was LDL （P 〈0. 01 ） . All the indexes but weight between high fat diet induced obese （HS- OB） rats and high fat diet induced obesity resistant （HS- OR） rats were no significant differences （P 〈 0. 05） . However, the levels of fasting blood glucose, insulin, IR index and LDL in high fat diet induced obesity resistant rats were significantly higher than those in normal control group. Conclusion： Although long - term high fat diet may not necessarily contribute to apparent increase of one weight. Sometimes they show obesity resistant. However, IR and disorders of lipid metabolism may still occur to them.