黄鳝血清睾酮和雌二醇含量周年变化规律的研究

THE ANNUAL CYCLE OF SERUM ESTRADIOL AND TESTOSTERONE IN SPONTANEOUS SEX-REVERSING FISH MONOPTERUS ALBUS (ZUIEW)

本研究采用放射免疫分析法,测定了311条黄鳝的血清性类固醇激素含量,其结果:雌、雄黄鳝**血清雌二醇(简称E_2)周年变化规律相关性明显(r=0.9594,p<0.01),均在5月份和10月份形成波峰。雌、雄黄鳝间血清睾酮(简称T)周年变化规律除3和4月份外相关性明显(r=0.7881,p<0.02)。同时还探讨了血清E_2含量与卵黄发生、血清T含量与精子发生和血清T含量与性反转的关系。

Level of serum E_2 (estradiol) in adult female Momopterus albus rose rapidly to the highest levle (2047.3±1668.9pg/mL) a month before spawing season; the average level of E_2 in spawing season (June to August) was about 218.5±72.0pg/mL, dropping to the lowest level a month after spawing,but there was slight increase in October and November. A positive correlation (r=0.9594, P<0.01) was found in profile of serum E_2 between male and female. Level of serum T (testosterone) in adult female increased to 802.14±553.8pg/mL in April, declining to 489.0±176.8pg/mL in May. The level of T was 753.1±97.7pg/mL in June and July. It fell significantly to 183.0±53.4pg/mL in August. There was a slight peak level of T in October. A positive correlation (r=0.7881, p<0.02) was found in serum T profiles between male and female. Significant increase of serum E_2 was in according with vitellogenesis a month before spawning season. Decline in E_2 level during spawning season indicated viteUogenesis completion. In males, increasing sharply in T level paralleled closely with spermatogenesis in the testes two month before spawning season, during the spawning season, high level of T coincided with spermatogenesis completion and sex behavious, respectively. In the females, annual reproductive cycle especially in Marth, April and October, high levels of serum T were correlated with the development of testicular tissues in the female's gonad.