减数分裂期雄性大菱鲆孕激素及受体基因的表达分析

摘要

To explore the function of progestin during spermatogonial proliferation and meiosis, we used histological methods to investigate the gonadal development process of the male turbot (Scophthalmus maximus) 6 to 22 months of age. We detected the expression of amh and sycp3 via the real-time quantitative polymerase chain reaction (qRT-PCR). Using enzyme-linked immunosorbent (ELISA) technology, qRT-PCR, and in-situ hybridization, we detected the serum P4 and DHP levels and the expression patterns of the nuclear progesterone receptor (pgr) and membrane progestin receptor alpha (mPRa) during different development periods. The results reveal that the P4 and DHP levels were high during spermatogonial proliferation and meiosis Ⅱ. The pgr expression was high from spermatogonial proliferation to meiosis I, whereas the mPRα expression was high during meiosis Ⅱ and spermiogenesis. Our in-situ hybridization results indicate pgr mRNA to be predominantly located in the Sertoli cells that were in contact with the proliferating spermatogonia and primary spermatocyte and that the mPRα mRNA was undetectable. Taken together, our data indi-cate the pgr expression to be involved in mediating the progestin stimulation of spermatogonia proliferation and meio-sis, whereas the mPRa plays an important role in meiosis Ⅱ and spermiogenesis.%为研究孕激素在大菱鲆(Scophthalmus maximus)精原细胞增殖到减数分裂过程中的作用,以6～22月龄的大菱鲆精巢为材料,通过组织学方法和定量amh、sycp3基因确定精原细胞增殖期和减数分裂期的大菱鲆精巢发育过程.通过酶联免疫吸附技术(ELISA)检测6～22月龄雄性大菱鲆血清中的孕酮(P4)和17α,20β,双羟孕酮(DHP)含量变化,利用qRT-PCR技术和原位杂交技术检测孕酮核受体(pgr)和膜受体(mPRα)在不同组织和不同发育时期的表达情况.结果表明孕激素在精原细胞增殖期高表达,开始出现初级精母细胞时降低,在精子细胞数量增加时表达量再次升高,在精子细胞变态形成精子时降低.pgr在减数分裂初期定位于精巢中的sertoli细胞,在精原细胞增殖至减数分裂期表达量逐渐增加,出现精子后显著降低;mPRα 在精原细胞增殖和初级精母细胞增加时表达量都很低,在精子细胞不断增加时显著增加.推测在精原细胞增殖和减数分裂阶段孕激素可能主要通过调节pgr的表达量来促进精巢发育,而在减数分裂 Ⅱ 期pgr和mPRα 都发挥作用,在精子细胞变态成熟时,主要是mPRα 发挥作用.