饮食诱导的肥胖发生前大鼠血清性激素水平探讨

A Study of the Levels of Serum Sex Hormones in Rats before Onset of Diet-induced Obesity

目的 探讨肥胖倾向和肥胖抵抗大鼠给予高脂饲料前血清性激素水平。方法 将雄性SD大鼠随机分成对照组和高脂组 ,采完血样后 ,分别用对照饲料和高脂饲料饲养 7周 ,高脂组大鼠根据体重增加程度分成肥胖倾向和肥胖抵抗两组。采用放射免疫分析方法检测给予高脂饲料前肥胖倾向和肥胖抵抗大鼠血清睾酮和雌二醇水平。结果 肥胖前 ,肥胖倾向大鼠血清睾酮水平 (0 5 0± 0 46nmol/L)显著低于肥胖抵抗大鼠(1 95± 1 70nmol/L)和对照组 (1 0 3± 0 47nmol/L)。 3组大鼠雌二醇水平没有显著差异。结论 在饮食诱导的肥胖发生前血清睾酮水平较低的大鼠可能易患饮食性肥胖。

Objective To determine whether there are different in obesity prone and obesity resistant rats before diet induced obesity occurs.Methods Male Sprague dawley rats were divided into control group and high fat group randomly.After initial blood sampling,rats were fed a control diet or a high fat diet for 7 weeks.Over the 7-wk period,rats fed the high fat diet diverged into two groups based on body weight gain.Serum testosterone and estradiol concentrations were determined in rats befor exposure to the high fat diet by radioimmunoassay.Results The obesity prone group had a low testosterone concentration before the onset of obesity(0 50±0 46nmol/L) compared with obesity resistant rats(1 95±1 70nmol/L) and control rats(1 03±0 47nmol/L).Estradiol levels were not different between the groups.Conclusion Low testosterone secretion exists before dietary challenge or before onset of obesity and may contribute to the susceptibility to obesity observed in these rats.