Osada Makoto, Tawarayama Hiroshi, Mori Katsuyoshi
Laboratory of Integrative Aquatic Biology, Field Science Center, Graduate School of Agricultural Science, Tohoku University, Onagawa, Oshika 986-2242, Japan.
Comp Biochem Physiol B Biochem Mol Biol. 2004 Sep;139(1):123-8. doi: 10.1016/j.cbpc.2004.07.002.
Aromatase activities and estrogen contents in the gonad of Japanese scallop, Patinopecten yessoensis, were determined during gonadal development and estrogenic cells in the testis were identified immunohistochemically. Ovaries and testes developed rapidly during January and February to reach the mature stage in March and the spawning stage in April. Increases in aromatase activities of the ovary and testis preceded the onset of the ovarian and testicular development. Aromatase activities reached the highest level at the growing stage in February and the mature stage in March, and showed a striking decrease at the spawning stage in April. Contents of ovarian and testicular estradiol-17beta changed similarly to the profile of aromatase activities in the ovary and testis, although estrone showed no change. Immunoreactivities against P450 aromatase and estradiol-17beta were detected in the cells along the inside of the acinar wall of the testis, whereas in the previous reports, the cells are distributed along the outside of the acinar wall in the ovary. This study thus suggests that estrogen is synthesized in the estrogenic cells of the ovary and testis through aromatization by P450 aromatase and that testicular estrogen may play a physiological role in spermatogenesis.
在虾夷扇贝性腺发育过程中，测定了其性腺中的芳香化酶活性和雌激素含量，并通过免疫组织化学方法鉴定了睾丸中的雌激素细胞。卵巢和睾丸在1月和2月迅速发育，3月达到成熟阶段，4月进入产卵阶段。卵巢和睾丸的芳香化酶活性增加先于卵巢和睾丸发育的开始。芳香化酶活性在2月的生长阶段和3月的成熟阶段达到最高水平，并在4月的产卵阶段显著下降。卵巢和睾丸中雌二醇-17β的含量变化与卵巢和睾丸中芳香化酶活性的变化相似，而雌酮则没有变化。在睾丸腺泡壁内侧的细胞中检测到了针对P450芳香化酶和雌二醇-17β的免疫反应性，而在之前的报道中，这些细胞分布在卵巢腺泡壁的外侧。因此，本研究表明雌激素是通过P450芳香化酶的芳香化作用在卵巢和睾丸的雌激素细胞中合成的，并且睾丸雌激素可能在精子发生中发挥生理作用。
