Schleicher G, Drews U, Stumpf W E
Max Planck Gesellschaft, University of Münster, F.R.G.
J Steroid Biochem. 1989 Feb;32(2):299-302. doi: 10.1016/0022-4731(89)90267-7.
Oestrogen receptors are found in the principal cells of the caput and in apical and clear cells of the epididymis of the mouse. The distribution pattern of oestrogen receptors is different from that of androgen receptors and suggests a physiological role for oestrogens in the epididymis. We examined by competition experiments and thaw-mount autoradiography to see whether aromatization of [3H]testosterone is the source of oestrogens in the epididymis. After injection of [3H]testosterone we found the same labeling pattern as after non-aromatizable [3H]dihydrotestosterone. In particular, apical and clear cells showed a low or no nuclear concentration of radioactivity as with [3H]dihydrotestosterone. Competition with oestradiol had no effect on the binding pattern of [3H]testosterone in the epididymis in contrast to its effects in the brain of the same animals. Competition with dihydrotestosterone abolished labeling in contrast to the brain, where no effect was observed. Thus no aromatization of [3H]testosterone to oestrogens but conversion to dihydrotestosterone seems to occur in the epididymis.
在小鼠附睾头的主细胞以及附睾的顶细胞和清亮细胞中发现了雌激素受体。雌激素受体的分布模式与雄激素受体不同，这表明雌激素在附睾中具有生理作用。我们通过竞争实验和解冻贴片放射自显影来研究[3H]睾酮的芳香化是否是附睾中雌激素的来源。注射[3H]睾酮后，我们发现其标记模式与注射不可芳香化的[3H]双氢睾酮后相同。特别是，顶细胞和清亮细胞显示出与[3H]双氢睾酮时相同的低放射性核浓度或无放射性核浓度。与雌二醇竞争对附睾中[3H]睾酮的结合模式没有影响，这与对同一动物大脑的影响形成对比。与双氢睾酮竞争则消除了标记，这也与大脑不同，在大脑中未观察到影响。因此，在附睾中似乎不会发生[3H]睾酮向雌激素的芳香化，而是会转化为双氢睾酮。
