Roberts V, Meunier H, Sawchenko P E, Vale W
Laboratory of Neuronal Structure and Function, Salk Institute, La Jolla, California 92037.
Endocrinology. 1989 Nov;125(5):2350-9. doi: 10.1210/endo-125-5-2350.
The distributions of the alpha-, beta A-, and beta B subunits of inhibin/activin polypeptides were studied in the testis of adult (60-day-old) and immature (12-day-old) rats. Immunohistochemical techniques using antisera selective for each subunit were used to localize the polypeptide chains. In situ hybridization using radiolabeled complementary RNA probes enabled localization of the messenger RNAs (mRNAs) encoding these subunits. In 12-day-old rats, immunostaining and mRNA signal for the alpha-subunit was found in Leydig cell clusters. The beta A- and beta B-subunit staining and beta A-subunit message were detectable in isolated interstitial cells, but the clusters appeared to lack these subunits. Positive immunostaining for each subunit was localized in a Sertoli cell-like pattern in seminiferous tubules, as was a positive mRNA signal for the alpha- and beta B-subunit over regions containing these cell types. Treatment with human CG (hCG) and PMSG greatly enhanced the production of the alpha-subunit in the Leydig cell clusters, but not within the tubules, of these young rats. In adult rats, alpha- and beta B-subunit staining, and alpha-subunit mRNA signal, was observed in the interstitial cells. As in the immature animals, all three subunits were localized in a Sertoli cell-like pattern in the tubules, and a positive mRNA signal for the alpha- and beta B-subunits was found over these cells. There was, however, no obvious change in the expression of the subunits in the testis of adult rats after gonadotropin treatment. The present findings suggest that: 1) in the rat testis, both Sertoli and interstitial cells produce inhibin/activin subunits; 2) the alpha- and beta-subunits are produced by different types of interstitial cells in immature rats; and 3) the production of the alpha-subunit in the Leydig cells of immature rats is regulated by LH-like hormones.
研究了抑制素/激活素多肽的α、βA和βB亚基在成年（60日龄）和未成年（12日龄）大鼠睾丸中的分布情况。使用对各亚基具有选择性的抗血清的免疫组织化学技术来定位多肽链。利用放射性标记的互补RNA探针进行原位杂交，从而能够定位编码这些亚基的信使RNA（mRNA）。在12日龄大鼠中，在睾丸间质细胞簇中发现了α亚基的免疫染色和mRNA信号。在分离的间质细胞中可检测到βA和βB亚基亚基染色以及βA亚基信息，但细胞簇似乎缺乏这些亚基。各亚基的阳性免疫染色以支持细胞样模式定位于生精小管中，α和βB亚基的阳性mRNA信号在含有这些细胞类型的区域也是如此。用人绒毛膜促性腺激素（hCG）和孕马血清促性腺激素（PMSG）处理这些幼鼠，可极大地增强睾丸间质细胞簇中α亚基的产生，但在小管内则不然。在成年大鼠中，在间质细胞中观察到α和βB亚基亚基染色以及α亚基mRNA信号。与未成年动物一样，所有三个亚基都以支持细胞样模式定位于小管中，并且在这些细胞上发现了α和βB亚基的阳性mRNA信号。然而，促性腺激素处理后成年大鼠睾丸中亚基的表达没有明显变化。目前的研究结果表明：1）在大鼠睾丸中，支持细胞和间质细胞均产生抑制素/激活素亚基；2）未成年大鼠中不同类型的间质细胞产生α和β亚基；3）未成年大鼠睾丸间质细胞中α亚基的产生受促黄体生成素样激素调节。
