来曲唑联合高脂饲料建立PCOS-IR大鼠模型实验研究

摘要

Objective To establish a rat model of polycystic ovary syndrome with insulin resistance (PCOS-IR) by using two different types of letrozole combined with high fat diet for different periods of time to analyze their endocrine and metabolic characteristics.Methods Eighteen 6-week-old female SD rats were randomly divided into 3 groups:control,the letrozole A group and the letrozole B group.The rats in control were fed with 0.5% carboxymethylcellulose solution daily.The rats in group A received letrozole for 21 consecutive days and fed with high-fat diet.Group B received letrozole for 30 days,feeding with high fat diet.The levels of follicle stimulating hormone (FSH),luteinizing hormone (LH),testosterone (T),triglyceride (TG) and fasting insulin (FINS) were measured and the changes of body weight and ovarian histology were observed.LH/FSH ratio and insulin resistance index (HOMA-IR) were calculated.Results Compared with the control,the body weight of letrozole A group increased significantly(P<0.05).The sex hormones and metabolic indexes were higher than that in the control (P<0.05),but there was no statistically significant difference (P>0.05).The weight of rats in group B was significantly higher than that in the control (P<0.05).The levels of T,LH/FSH,TG,FPG,FINS and HOMA-IR were significantly increased (P<0.01).Conclusion Letrozole combined with high fat diet for 30 days can successfully induce a rat model of polycystic ovary syndrome with insulin resistance.%目的 采用两种不同喂养时间的来曲唑联合高脂饲料方法,建立多囊卵巢综合征胰岛素抵抗(polycystic ovary syndrome with insulin resistance,PCOS-IR)大鼠模型,分析两种模型各自的内分泌和代谢特征.方法 将18只6周龄SD雌性大鼠采用数字表法随机分为3组:对照组、来曲唑A组和来曲唑B组,每组各6只.对照组予普通饲料喂养,每日灌胃0.5%(质量分数)羧甲纤维素钠溶液;来曲唑A组连续21 d灌胃来曲唑溶液,同时给予高脂饲料喂养;来曲唑B组连续30 d灌胃来曲唑溶液,并给予与来曲唑A组相同的高脂饲料喂养.观察3组大鼠的体质量和卵巢组织学变化,测定血清卵泡刺激素(follicle stimulating hormone,FSH)、黄体生成素(luteinizing hormone,LH)、睾酮(testosterone,T)、三酰甘油(triglyceride,TG)和空腹胰岛素(fasting insulin,FINS)等浓度,计算LH/FSH比值和胰岛素抵抗指数(homeostasis model of assessment for insulin resistence index,HOMA-IR).结果 与对照组比较,来曲唑A组大鼠体质量明显增加,差异有统计学意义(P<0.05),性激素及代谢等指标较对照组有升高趋势,但差异无统计学意义(P>0.05).来曲唑B组大鼠的体质量亦有明显增加(P<0.05),卵巢呈多囊样改变,血清T、LH/FSH显著升高(P<0.01),同时,三酰甘油、空腹血糖(fasting plasma glucose,FPG)、空腹胰岛素和HOMA-IR值均显著升高(P<0.01).结论 来曲唑联合高脂饲料喂养30 d可成功诱导出多囊卵巢综合征胰岛素抵抗大鼠模型;与同法喂养21 d的模型相比,其内分泌与代谢指标改变更符合人PCOS-IR的临床病理特征.