Ultee-van Gessel A M, Leemborg F G, de Jong F H, van der Molen H J
J Endocrinol. 1985 Aug;106(2):259-65. doi: 10.1677/joe.0.1060259.
Pituitary secretion of FSH in male animals is regulated, at least partly, by a protein hormone, inhibin, which is produced by Sertoli cells in the testes. To establish at which age the role of testicular inhibin in the regulation of FSH secretion becomes apparent, groups of male rats were hemicastrated or sham-operated on day 1 of life and pituitary and testicular function were investigated in vitro at 21, 42 or 63 days of age. Testis weights were increased in hemicastrated rats at all ages studied. Peripheral concentrations of gonadotrophins generally showed a good correlation with the concentrations of FSH and LH measured in the medium of hemipituitary glands which were incubated in vitro at 37 degrees C in the absence or presence of LH-releasing hormone. Peripheral testosterone concentrations in hemicastrated animals were not significantly different from those in sham-operated rats at all ages studied. Steroid production by Leydig cells in vitro was not significantly influenced by hemicastration. The secretion of inhibin by Sertoli cells from 21-day-old hemicastrated rats was decreased while Sertoli cells from 42- and 63-day-old hemicastrated animals secreted slightly but not significantly more inhibin than Sertoli cells from sham-operated rats. It is concluded that although compensatory increases of testosterone and inhibin production at later ages make it difficult to draw conclusions about the relative importance of inhibin in the feedback regulation of FSH secretion at different ages, it is likely that inhibin plays a role in the feedback of FSH in immature, rather than in mature male rats.
雄性动物垂体促卵泡激素（FSH）的分泌至少部分受一种蛋白质激素抑制素调节，该抑制素由睾丸中的支持细胞产生。为确定睾丸抑制素在FSH分泌调节中的作用在哪个年龄段变得明显，在出生第1天对雄性大鼠分组进行半阉割或假手术，并在21、42或63日龄时体外研究垂体和睾丸功能。在所研究的所有年龄段，半阉割大鼠的睾丸重量均增加。促性腺激素的外周浓度通常与在37℃下于有无促黄体生成素释放激素的情况下体外孵育的半垂体培养基中测得的FSH和LH浓度具有良好的相关性。在所有研究的年龄段，半阉割动物的外周睾酮浓度与假手术大鼠的外周睾酮浓度无显著差异。半阉割对体外睾丸间质细胞的类固醇生成无显著影响。21日龄半阉割大鼠的支持细胞分泌的抑制素减少，而42日龄和63日龄半阉割动物的支持细胞分泌的抑制素比假手术大鼠的支持细胞略有增加，但不显著。结论是，尽管后期睾酮和抑制素产生的代偿性增加使得难以就抑制素在不同年龄段FSH分泌反馈调节中的相对重要性得出结论，但抑制素可能在未成熟而非成熟雄性大鼠的FSH反馈中起作用。
