日本鰻肝臟與卵巢離體培養下雄性激素接受器之表現

Abstract

中文摘要

在日本鰻人工催熟的策略中使用外源性荷爾蒙(salmon pituitary homogenate, SPH)，可以使之生殖成熟達到排卵，另一方面SPH與雄性激素共同注射的鰻魚，在本實驗室研究成果中，發現有更多顯著的優點，如卵數較多、卵發育較為同步等優點。性荷爾蒙，如雄性激素扮演一部分在於腦部，下視丘與腦下腺的回饋作用等。在本實驗室過去的外源性注射鰻魚研究當中，以SPH與雄性激素催熟，卻尚未能了解雄性激素如何在卵巢與肝臟進行作用，本實驗因而在日本鰻人工催熟的早期，採用離體組織培養的方式分別探討SPH與雄性激素單一與相加對於肝臟與卵巢，雄性激素接受器(androgen receptor, AR)，雌性激素接受器(estrogen receptor, ER)與卵黃前質(vitellogenin, Vg)的表現，透過測定雄性激素接受器來呈現雄性激素對於卵巢與肝臟的影響，並且觀察雄性激素接受器如何表現，在本篇研究中發現以SPH注射一針的日本鰻，ARs與ER之表現量提升，在使用雄性激素離體培養的日本鰻卵巢與肝臟中，ARs與ER表現量皆有提高，並且在卵巢中增加follicle-stimulating hormone receptor, FSHR的表現量；然而以SPH注射一針持續使用SPH培養的組別卻使ARs與ER之表現量下降。在日本鰻的人工催熟中持續注射SPH可以使鰻魚青春發育完成並且達到最後的成熟，持續的SPH可能於早期會抑制其雄性激素接受器或是其他接受器的表現量，可能使Vg生成量降低，進而影響卵質。本篇實驗藉由離體培養，印證了過去的使用SPH與雄性激素催熟，在人工催熟早期，雄性激素不僅只進行回饋作用，在肝臟與卵巢扮演了不可或缺的角色，提升雄性激素接受器的表現，肝臟中vitellogenesis與卵巢中FSHR的表現，人工催熟的策略中使用SPH與雄性激素對於日本鰻生殖成熟發育有正面的幫助。

Abstract

In the artificial maturation of Japanese eel by treating salmon pituitary homogenate (SPH) is an effective way to induce oocytes to ovulate and be fertilizable. Furthermore co-treatment of SPH and androgen, this tactic has more obvious advantages, such as more quantity of oocytes and synchronizing development of oocytes etc. Generally, sexual steroids play a part of role in the feedback in brain, hypothalamus and pituitary. In the situation of in vivo experiments, using SPH and androgen for eel maturation could not explain androgen if there are direct affects between liver and ovary. In this study, we use the in vitro way treating SPH and androgen and culturing ovary and liver tissues to measure the expressions of androgen receptor (AR), estrogen receptor (ER), and vitellogenin (Vg). By the expression of ARs, we can judge how the androgen influencing liver or ovary. We take Japanese eels SPH injected one time and changed into sea water in vivo for liver and ovary tissue culture in vitro. In the culturing groups treating androgen, the expressions of ARs, ER and follicle-stimulating hormone receptor (FSHR) increased, but in the groups treating continuous SPH, the expressions of ARs and ER decreased. The androgen can help the expression of ARs, ER, FSHR and Vg increased and the continuous treating SPH decrease these receptors expressions. This study manifest our suppose the androgen have direct and positive effects in eel artificial maturation especially in the early maturation period and not only just play the role of feedback in the brain of female Japanese eels.