肥胖大鼠的胰岛素抵抗指数与血脂的相关性观测

Observation on Correlation between Insulin Resistance Index and Blood Lipid in Obese Rats

目的通过高脂饮食诱导建立肥胖大鼠模型,观测肥胖大鼠血脂等生化指标与胰岛素抵抗的相关性。方法采用36%脂肪供能的高脂饲料持续喂养雄性SD大鼠12周,检测摄食量,观测大鼠体质量,计算Lee's指数,多时间段收集血清测定血清胰岛素(Fins)、空腹血糖(FBG)、总胆固醇(TC)、甘油三脂(TG)、高密度脂蛋白胆固醇(HDL-C)及低密度脂蛋白胆固醇(LDL-C)水平,求算胰岛素抵抗指数(HOMA-IR)。聚类分析筛选产生胰岛素抵抗的大鼠,分析其生化指标与正常组的差异。结果高脂饲料诱导大鼠4周后产生肥胖,体质量、Lee's指数显著升高(P<0.01, P<0.05)。以肥胖大鼠12周末HOMA-IR为筛选条件,通过聚类分析选出产生胰岛素抵抗的大鼠16只,经统计学处理,与正常组相比,16只大鼠8周后即产生胰岛素抵抗(P<0.05),TC和HDL-C显著下降(P<0.05, P<0.01),但FBG、TG、LDL-C水平无显著改变。结论采用36%脂肪供能高脂饲料诱导的肥胖大鼠在8周末出现50%大鼠产生胰岛素抵抗,胰岛素抵抗大鼠的脂代谢发生明显紊乱。

Objective To obesrve the correlation between blood lipids and insulin resistance in obese rats induced by high-fat diet.Methods Male Sprague-Dawley rats were continuously fed with high fat diet supplemented with 36% fat energy for 12 weeks.The food intake,body weight were detected,Lee’s index was calculated,serum which was collected by multiple time periods and the degrees of serum insulin,fasting blood glucose,total cholesterol(TC),triglyceride(TG),high density lipoprotein cholesterol(HDL-C) and low density lipoprotein cholesterol(LDL-C) were measured,and insulin resistance index was calculated.Cluster analysis was used to screen successful insulin resistance rats and their differences in body weight,Lee’s index,biochemical indicators compared to normal groups were analysed.Result Rats induced by high-fat diet developed obesity after 4 weeks with higher levels of body weight and Lee’s index(P<0.01,P<0.05).Sixteen rats producing insulin resistance were selected by cluster analysis based on the 12-week insulin resistance index of obese rats.After statistical analysis,16 rats developed insulin resistance after 8 weeks,with lower levels of TC and HDL-C as compared with the normal group(P<0.05).But there was no significant change in FBG,TG and LDL-C contents.Conclusion Obese rats induced by 36% fat-energy high-fat diet began to produce insulin resistance with about 50% of the obese rats at the end of the 8 th week and the lipid metabolism were significantly disordered in insulin resistance rat.