雄烯二酮和甲基睾酮诱导雌性日本鳗鲡性腺发育的反馈调节作用

The feedback effects of 4 androstene 3,17 dine and 17α methyl testosterone on gonadal development in the female Anguilla japonica

采用间隔 15d多次埋植雄激素雄烯二酮 (4 androstene 3 ,17 dine ,ADSD)或甲基睾酮 (17α methyl testosterone ,MT)诱导雌性日本鳗鲡 (Anguillajaponica)性腺发育成熟 ;并着重研究埋植雄激素后 ,雌鳗血清中促性腺激素 (GtH)及脑和垂体中哺乳类促性腺激素释放激素 (mGnRH)含量的动态变化。一次或多次埋植ADSD后 ,1～ 5d的血清GtH含量上升 ,然后下降 ;并且 ,血清GtH含量上升的幅度随埋植次数的增加而增加 ;对于MT处理组 ,只在埋植 7次后第 15天测得血清GtH水平显著高于对照组 ,但仍显著低于ADSD处理组。这表明埋植ADSD和MT可促进GtH的分泌 ,但两者促进GtH分泌的作用存在显著差异。埋植ADSD 1d后 ,脑和垂体中mGnRH含量明显增加 ,第 2天后和对照组无明显差别 ,表明ADSD促进了mGnRH的合成 ,并可能有一定程度的释放。

The effects of 4 androstene 3,17 dine (ADSD) and 17α methyl testosterone (MT) via implantation on maturation of the female silver eel, Anguilla japonica and their kinetic effects on serum GtH levels, brain and pituitary GnRH levels were studied. Serum GtH levels increased during the period of 1-5 days after implantation of ADSD, and the responses elevated with increasing times of implantation of ADSD. Implantation of MT, however, did not increase serum GtH levels significantly, except on the 15th day after 7 times of implantation. These results indicated that implantation of ADSD and MT stimulated the secretion of GtH, and there was a difference in effect between ADSD and MT. A single ADSD implantation significantly increased mGnRH contents in the brain and pituitary one day after treatment, but two days later, mGnRH contents in the brain and pituitary returned to the levels of the controls, indicating that implantation of ADSD stimulated the mGnRH synthesis and secretion. Thus, androgen have positive feedback effects at the brain and pituitary level to stimulate gonadal development in the female silver eel.