作　　者： ; ; ; ; ;

机构地区： 中山大学生命科学学院水生经济动物研究所

出　　处： 《动物学报》 2006年第2期316-327,共12页

摘　　要： 采用腹部埋植法,应用连续组织切片技术、放射免疫测定方法和半定量RT-PCR技术,检测了间隔30d3次埋植不同剂量(高剂量H:100μg/g体重,低剂量L:10μg/g体重)的雄烯二酮(4-androstene-3,17-dine,ADSD)诱导2龄赤点石斑鱼性腺发育过程中血清性类固醇激素含量、芳香化酶表达和活性的变化。结果显示:第1次埋植ADSD后30d即可诱导雌性赤点石斑鱼发生不同程度的性逆转,性腺成熟指数明显下降,性腺中卵细胞退化,精原细胞增殖,出现大量精母细胞和精子细胞,第1次埋植ADSD后30d经轻微挤压腹部有10%(低剂量组)和15%(高剂量组)的鱼可排精;第2次埋植后30d明显提高性逆转效果,排精率分别达到80%和86·7%,性逆转雄鱼的精巢在组织结构上与正常雄鱼精巢一样,精子活力与正常雄鱼相同,对照组鱼卵巢发育良好;第3次埋植后30d排精率分别为90%和80%,埋植ADSD后性腺芳香化酶(P450aromA)表达和活性显著降低,脑芳香化酶(P450aromB)表达显著升高,前脑芳香化酶活性显著升高,血清T,11-KT水平显著高于对照组,而血清E2水平先升高,然后逐渐降低。说明血清T,11-KT水平增加,性腺芳香化酶表达及活性降低在控制雌雄同体的赤点石斑鱼的性转化和精子发生中起重要作用[动物学报52(2):316-327,2006]。 Through the detection methods of histology, radioimmunoassay （RIA） and RT-PCR, the effects of various dose of ADSD via implantation on sex steroid contents, aromatase expression and activity in 2-year-old red-spotted groupe Epinephelus akaara were examined. Groupers were divided into three groups, one implanted with high 4-androstene-3, 17-dine （ADSD, 100 μzg/g body weight ）, the second with low ADSD （ 10 μg/g body weight） and the third without ADSD once 30d for 3 months. The results indicated sex inversion in ADSD-implanted group. Fish implanted with ADSD once （for 30 d） showed significantly lower GSI and complete degradation of oocytes and developing testicular tissues. ADSD induced females to develop into functionalimales, these males had testes, which were similar in structure from those of normal males. Spermiating rates of induced males in ADSD-implanted group as follows： 15%, 86.7% and 80% （high dose group）, or 10% , 80% and 90% （low dose group） at the 30 d, 60 d, and 90d, respectively, and the sperm motility was the same between the control and ADSD-implantation, while all fish in the control were still female with developing ovaries. Aromatase expression and activity decreased significantly in the gonad, increased significantly in forebrain, respectively, after ADSD implanted. Serum estradiol-17β （E2） levels began to increase after ADSD-implantation, then decreased gradually in ADSD-treated group, while serum levels of testosterone （T） and 11-ketotestosterone （11-KT） concentration increased significantly. The results suggest that the increase of serum T, 11-KT levels and gonadal aromatase expression and activity may be important to the controlled male phase in protogynous red-spotted grouper, E. akaara .

关 键 词： 赤点石斑鱼 雄烯二酮 性逆转 性类固醇激素 芳香化酶表达和活性

领　　域： [生物学] [农业科学] [农业科学]