不同发育时期雄性鳗鲡精巢和GtH分泌细胞的结构观察及相关组织中性类固醇激素的变化

Histological and ultrastructural observation of testis and GtH cell and quantification of sexual steroid hormones in the male Japanese eel during artificially induced maturation

通过组织切片和电子显微镜观察经多次注射人绒毛膜促性腺激素(human chorionic gonadotropin,hCG)和鲤鱼脑垂体匀浆液(carp pituitary extract,CPE)促熟的雄性鳗鲡(Anguilla japonica)精巢和脑垂体超微结构的变化,并采用超高效液相色谱-串联质谱(UPLC/MS/MS)联用的方法,观察性腺和血液中7种类固醇激素含量的变化。结果发现:成熟组鳗鲡精巢发育至第Ⅴ期,排精10 d时鳗鲡精巢进入退化吸收期。性成熟雄性鳗鲡的脑垂体GtH分泌细胞代谢活动旺盛,细胞中分泌小球增多,囊泡数量增加,线粒体和内质网丰富。鳗鲡精巢和血液中睾酮(testosterone,T)、17α,20β-二羟基-4-孕烯-3-酮(17α,20β-dihydroxy-4-pregnen-3-one,DHP)和17α-羟孕酮(17α-hydroxyprogesterone,17α-OHP)3种激素含量较高,且成熟的和排精10 d后雄鱼精巢和血液中T、DHP和17α-OHP的含量均显著高于对照组(P﹤0.05),排精10 d时雄鱼精巢和血液中17α-羟孕酮的含量显著低于成熟组鳗鲡精巢和血液中的含量(P﹤0.05);精巢和血液中未检出孕酮(progesterone,P)、雌酮(estrone,E1)、β-雌二醇(estradiol-17β,E2)和雌三醇(estriol,E3)4种激素。结果表明,睾酮、17α-羟孕酮和DHP是雄鱼成熟的关键类固醇激素,其含量在性成熟时达到峰值,排精10 d时含量降低,其含量受脑垂体GtH分泌的调控。

In this paper,histological and electron microscopy observations of the testis and GtH cells were conducted,and ultra-performance liquid chromatography coupled with electronspry ionization-triple quadruple mass spectrometry（ UPLC / MS / MS） method was applied to determine the content and changes of 6 steroid hormones in the testis of male farmed mature eels during artificially induced maturation through carp pituitary extract and h CG injection. The results showed that the eel testis developed to fully mature and then absorbed and degraded 10 days post spermiation. The contents of progesterone（ P）,estradiol-17β（ E2） and estriol（ E3）were below limit of detection. The average contents of testosterone（ T）,17α,20β-dihydroxy-4-pregnen-3-one（ DHP）,and 17α-hydroxypro-gesterone（ 17α-OHP） were significantly higher than those in the control group.The results indicated that the contents of T,DHP and 17α-OHP were low in the control group,and increased during spermiation and then decreased after spermiation in male eel. The results showed that 17α-OHP,T and DHP might be key elements during testis maturation which are regulated by GtH secretion in the pituitary gland.