In European aquaculture, Eurasian perch, Perca fluviatilis L., is perceived as one of the most highly valuable freshwater fish species and a strong candidate for the development of freshwater aquaculture. In the pursuit of improving the quality of reproduction in this domesticated species, investigating the hormones mediating the final oocyte maturation (FOM) is therefore indispensable. But, the exact nature of the maturation-inducing hormone (MIH) in Eurasian perch is unknown. To further validate the existence of a maturation-inducing activity behind potential hormonal candidates in this species, we in vitro tested a group of nine hormones: cortisol (Co), 11-deoxycortisol (11-D), corticosterone (coS), 11-deoxycorticosterone (DOC), 17α,20βdihydroxy-4-pregnen-3-one (DHP) and 17α,20β,21 trihydroxy-4-pregnen-3-one (THP), prostaglandin E₂ (PGE2), estradiol-17β (E2) and testosterone (T), in their ability to trigger FOM advancement and the production of sex steroids potentially involved in FOM. Using mature female perch, two in vitro experiments were conducted with oocytes at the start of the FOM. The follicles were incubated for 62 h in Cortland media with and without human chorionic gonadotropin (hCG). By the end of the incubation, only DHP and THP triggered the full advancement in FOM even at low doses with the effect of DHP being in vivo validated. However, the de novo productions of E2 and DHP were not shown to be regulated by either of the MIH candidates. Progestagens are hence more credible candidates as MIH than corticosteroids in Eurasian perch. Our in vitro study also revealed that both PGE2 and DHP are strongly associated with ovulation and that PGE2 might have slightly contributed to such DHP activity.

在欧洲水产养殖中，欧亚鲈鱼，Perca fluviatilisL.，被认为是最有价值的淡水鱼类之一，也是发展淡水水产养殖的有力候选者。因此，为了提高这种驯化物种的繁殖质量，研究介导最终卵母细胞成熟 (FOM) 的激素是必不可少的。但是，欧亚鲈鱼成熟诱导激素 (MIH) 的确切性质尚不清楚。为了进一步验证该物种潜在激素候选物背后的成熟诱导活性的存在，我们在体外测试了一组九种激素：皮质醇 (Co)、11-脱氧皮质醇 (11-D)、皮质酮 (coS)、11-脱氧皮质酮 (DOC)、17α,20βdihydroxy-4-pregnen-3-one (DHP) 和 17α,20β,21 trihydroxy-4-pregnen-3-one (THP)、前列腺素 E ₂(PGE2)、雌二醇-17β (E2) 和睾酮 (T)，它们能够触发 FOM 进展和可能参与 FOM 的性类固醇的产生。使用成熟的雌性鲈鱼，在 FOM 开始时用卵母细胞进行了两次体外实验。将卵泡在含有或不含人绒毛膜促性腺激素 (hCG) 的 Cortland 培养基中培养 62 小时。到孵化结束时，即使在低剂量下，也只有 DHP 和 THP 触发了 FOM 的全面进步，DHP 的效果在体内得到了验证。然而，E2 和 DHP 的从头生产并未显示出受任何一个 MIH 候选者的调控。因此，孕激素作为 MIH 的候选者比欧亚鲈鱼的皮质类固醇更可靠。