Uchida Daisuke, Yamashita Michiaki, Kitano Takeshi, Iguchi Taisen
Graduate School of Integrated Science, Yokohama City University, Seto, Kanazawa-ku, 236-0027, Yokohama, Japan.
Comp Biochem Physiol A Mol Integr Physiol. 2004 Jan;137(1):11-20. doi: 10.1016/s1095-6433(03)00178-8.
Dietary administration of a cytochrome P450 aromatase (P450arom) inhibitor (fadrozole) in genetic female juveniles of zebrafish (Danio rerio) was performed at 15-40 days post-hatching. The percentage of gonadal masculinization in the genetic all-females at 40 days post-hatching, treated with 0, 10, 100 and 1000 microg fadrozole g(-1) diet(-1) were 0, 62.5, 100 and 100%, respectively. Rearing at high water temperature in genetic all-females was performed at 15-25 days post-hatching. The percentage of gonadal masculinization in the genetic all-females at 40 days post-hatching, at water temperatures of 28.5, 35 and 37 degrees C were 0, 68.8 and 100%, respectively. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive oocytes of early diplotene and perinucleolar stages in fadrozole-treated genetic females (1000 microg g(-1) diet(-1)) were observed at 15-40 days post-hatching during sex-reversal. In contrast, apoptotic oocytes of early diplotene stage in high temperature-treated genetic females (at 35 and 37 degrees C) during sex-reversal and presumptive males of wild-type fish during sex differentiation were found at 15-27 days post-hatching. Our findings indicate that oocyte apoptosis, depletion of P450arom activity and differentiation of spermatogonia during gonadal sex-reversal are caused by treatments of aromatase inhibitor or high water temperature.
在斑马鱼（Danio rerio）遗传雌性幼鱼孵化后15至40天，对其进行细胞色素P450芳香化酶（P450arom）抑制剂（法倔唑）的饮食给药。在孵化后40天，用0、10、100和1000微克法倔唑/克饲料处理的遗传全雌性鱼的性腺雄性化百分比分别为0、62.5%、100%和100%。在遗传全雌性鱼孵化后15至25天，将其置于高温水中饲养。在孵化后40天，水温为28.5、35和37摄氏度时，遗传全雌性鱼的性腺雄性化百分比分别为0、68.8%和100%。在性逆转期间，于孵化后15至40天观察到，经法倔唑处理的遗传雌性鱼（1000微克/克饲料）处于双线期早期和核仁周围期的末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（TUNEL）阳性卵母细胞。相比之下，在性逆转期间，高温处理的遗传雌性鱼（35和37摄氏度）处于双线期早期的凋亡卵母细胞以及在性别分化期间野生型鱼的推定雄鱼在孵化后15至27天被发现。我们的研究结果表明，性腺性逆转期间的卵母细胞凋亡、P450arom活性的耗尽以及精原细胞的分化是由芳香化酶抑制剂处理或高温引起的。
