PDF(Pubmed)
Abstract：
Previous studies have suggested that the effects of androgens on body weight (BW) and appetite are affected by the estrogen milieu in females; however, the mechanism underlying these effects remains unclear. We hypothesized that androgens may affect endogenous oxytocin (OT), which is a hypothalamic anorectic factor, and that these effects of androgens may be altered by the estrogen milieu in females. To investigate this hypothesis, in the present study, we examined the effects of testosterone on peripheral and central OT levels in ovariectomized female rats that did or did not receive estradiol supplementation. Ovariectomized female rats were randomly divided into non-estradiol-supplemented or estradiol-supplemented groups, and half of the rats in each group were concurrently supplemented with testosterone (i.e., rats were divided into four groups, n = 7 per each group). We also measured peripheral and central OT receptor (OTR) gene expression levels. As a result, we found that testosterone increased serum and hypothalamic OT levels and OT receptor mRNA levels in non-estradiol-supplemented rats, whereas it had no effects on these factors in estradiol-supplemented rats. In addition, testosterone reduced food intake, BW gain, and fat weight in non-estradiol-supplemented rats, whereas it did not have any effects on BW, appetite, or fat weight in estradiol-supplemented rats. These findings indicate that the effects of androgens on OT may be affected by the estrogen milieu, and elevated OT levels may be related to the blunting of appetite and prevention of obesity under estrogen-deficient conditions.
摘要：
以前的研究表明，雄激素对体重（BW）和食欲的影响受女性雌激素环境的影响；然而，这些效应的潜在机制尚不清楚.我们假设雄激素可能影响内源性催产素（OT），这是一种下丘脑厌食因素，雄激素的这些作用可能会被女性的雌激素环境所改变。为了研究这个假设，在本研究中，在接受或未接受雌二醇补充的去卵巢雌性大鼠中,我们研究了睾酮对外周和中枢OT水平的影响.将去卵巢雌性大鼠随机分为不补充雌二醇或补充雌二醇组,每组一半的大鼠同时补充睾酮(即，大鼠分为四组，每组n=7)。我们还测量了外周和中枢OT受体(OTR)基因表达水平。因此,我们发现，睾酮增加血清和下丘脑OT水平和OT受体mRNA水平在非雌二醇补充的大鼠，而在补充雌二醇的大鼠中，它对这些因素没有影响。此外,睾酮降低食物摄入量，BW增益,非雌二醇补充大鼠的脂肪重量，虽然它对BW没有任何影响，食欲,或补充雌二醇的大鼠的脂肪重量。这些发现表明，雄激素对OT的影响可能受到雌激素环境的影响，在雌激素缺乏的情况下，升高的OT水平可能与食欲减弱和预防肥胖有关。
