食源性肥胖对SD大鼠生殖能力的影响

The Effect of Diet- induced Obesity on Reproductive Capacity of the Rat

目的探讨食源性肥胖对SD大鼠生殖能力影响及其可能的机制。方法 60只6周龄的SD雌性大鼠,采用高脂肪、高热量食物饲喂2周,根据体质量选择肥胖倾向的大鼠20只作为肥胖组(OG组),同周龄的另20只SD大鼠作为对照组(NG组),分别给予高脂饮食和普通饲料饲喂6周后,与雄鼠合笼交配1周,继续喂养直至孕鼠分娩。观察交配前的体质量和Lee’s指数,以及血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、血清瘦素(leptin)和雌二醇(E2)的水平,并比较两组的妊娠率、平均子鼠数量和平均鼠出生体质量。结果饲喂6周后OG组体质量和Lee’s指数显著高于NG组(P﹤0.01);OG组大鼠妊娠率明显低于NG组(P﹤0.01);OG组大鼠TC、TG和LDL-C水平均显著高于NG组(P﹤0.01);OG组大鼠血清leptin水平较NG组明显升高(P﹤0.01)。结论高脂、高热量饮食诱导的SD大鼠食源性肥胖模型,其生殖能力降低,可能与leptin水平升高有关。

Objective To probe into the effect of diet-induced obesity on reproductive capacity of SD rat. Method 60 female SD rats aged 6 weeks were fed with high-fat and high-calorie feed for 2 weeks, and then 20 obesity- prone rats were selected according to their weight as the obesity group and other 20 rats were selected as the control group. The rats in the obesity group were fed with high-fat and high-calorie feed for 6 weeks to induce obesity and the rats in the control group were fed with ordinary rat feed. Before mating the body weights were measured and Lee＇ s index was calculated, and the levels of total cholesterol （TC） , triglyceride （TG） , high density lipoprotein cholesterol （HDL-C）, low density lipoprotein cholesterol （LDL-C）, leptin and estradiol （E2） in serum were determined. These female rats were mated with the male rats for one week, and the pregnancy rate and litter size were checked. Result The pregnancy rate in rats of the obesity group was significantly lower than that in the control group （P 〈0.01 ）. After the feeding for six weeks, the weight and Lee＇s index of the Obesity group rats were significantly higher than those of the control group （P 〈 0.01 ） , and the serum levels of TC, TG, LDL-C and leptin in the obesity group were significantly higher than those in the control group （P 〈 0.01 ）. Conclusion The high-fat and high-calorie diet-induced rat declined in reproductive capacity, which may be related to the elevation in the serum level of leptin.