Carpino A, Pezzi V, Rago V, Bilinska B, Andò S
Dipartimento di Biologia Cellulare, Università degli Studi della Calabria Cosenza, Italy.
Tissue Cell. 2001 Aug;33(4):349-53. doi: 10.1054/tice.2001.0186.
Aromatization of androgens into estrogens in rat testis is catalyzed by the microsomal enzyme cytochrome P450 aromatase. In this work, aromatase cellular site was investigated in prepuberal, peripuberal and postpuberal testis, from 10-, 21- and 60-day-old rats respectively. Paraffin-embedded testis sections were processed for P450arom immunostaining using a rabbit polyclonal antiserum generated against purified human placental cytochrome P450 aromatase. Next, biotinylated anti-rabbit IgG was applied, followed by ABC/HRP/complex amplification with diaminobenzidine as chromogen. Prepuberal testis sections showed a strong immunoreactivity of aromatase in Sertoli cell cytoplasm while interstitial cells were immunonegative. In peripuberal testis sections, cytoplasmic immunoreaction was weak in Sertoli cells, but it was strong in spermatocytes and sporadic in Leydig cells. Postpuberal testis sections displayed a moderate aromatase immunoexpression in spermatocytes while a strong immunostaining was observed in round and elongated spermatids, as well as in Leydig cells. These results indicate a different age-dependence of aromatase localization in rat testicular cells during gonadal development. In particular, inside the seminiferous tubules, the aromatization site moves from Sertoli cells to late germ cells, suggesting a proliferative role of aromatase in prepuberal testis and its subsequent involvement in meiotic and post-meiotic germ cell maturation.
大鼠睾丸中雄激素向雌激素的芳香化作用由微粒体酶细胞色素P450芳香化酶催化。在本研究中，分别对10日龄、21日龄和60日龄大鼠青春期前、青春期中和青春期后的睾丸进行了芳香化酶细胞定位研究。使用针对纯化的人胎盘细胞色素P450芳香化酶产生的兔多克隆抗血清，对石蜡包埋的睾丸切片进行P450arom免疫染色。接下来，应用生物素化的抗兔IgG，然后用二氨基联苯胺作为显色剂进行ABC/HRP/复合物放大。青春期前睾丸切片显示支持细胞胞质中芳香化酶有强烈免疫反应性，而间质细胞免疫阴性。在青春期中睾丸切片中，支持细胞胞质免疫反应较弱，但在精母细胞中较强，在睾丸间质细胞中呈散在分布。青春期后睾丸切片显示精母细胞中有中度芳香化酶免疫表达，而在圆形和长形精子细胞以及睾丸间质细胞中观察到强烈免疫染色。这些结果表明，在性腺发育过程中，大鼠睾丸细胞中芳香化酶的定位存在不同的年龄依赖性。特别是，在生精小管内，芳香化作用位点从支持细胞转移到晚期生殖细胞，这表明芳香化酶在青春期前睾丸中具有增殖作用，随后参与减数分裂和减数分裂后生殖细胞的成熟。
