Venkatasubramanian Hemagowri, Selvaraj Velanganni, Ramasamy Mohankumar, Santhakumar Kirankumar
1 Zebrafish Genetics Laboratory, Department of Genetic Engineering, SRM Institute of Science and Technology, Chennai, India.
2 Interdisciplinary Institute of Indian System of Medicine, SRM Institute of Science and Technology, Chennai, India.
Zebrafish. 2019 Apr;16(2):139-151. doi: 10.1089/zeb.2018.1595. Epub 2018 Dec 4.
Induction of all-male population in Siamese fighting fish, Betta splendens, has potential application in ornamental fish trade. In addition, the sexually dimorphic nature of aggressive behavior exhibited by this species has made it into an emerging model for behavioral studies. Fadrozole, an aromatase inhibitor, which has been used widely in masculinization, has captivated us to use it in this study. Twenty one days postfertilization (dpf), B. splendens fry were subjected to discrete immersion treatment with various concentrations of fadrozole, and eventually, analyses of various socioreproductive behaviors and analyses of stress markers such as dopamine in brain samples, sex hormones, cortisol, and glucose in plasma samples were performed. We observed that 91% of 50 μg/L fadrozole treated fish developed as males. Interestingly, reproductive analyses of these males gave rise to two subgroups (A and B). Subsequent sociobehavioral analyses demonstrated a timid and subdued behavior in subgroup B males. Furthermore, estimation of stress markers such as dopamine levels in the brain tissue, cortisol, and glucose levels in blood plasma and sex hormone levels in blood plasma exhibited an endocrine disruption-mediated stress leading to altered behavior in these males. These findings will help in understanding the fadrozole-mediated masculinization and behavioral alterations following endocrine disruption.
暹罗斗鱼（Betta splendens）全雄群体的诱导在观赏鱼贸易中具有潜在应用价值。此外，该物种所表现出的攻击行为的两性异形特性使其成为行为研究的新兴模型。芳香化酶抑制剂法倔唑已广泛用于雄性化过程，这促使我们在本研究中使用它。在受精后21天（dpf），用不同浓度的法倔唑对暹罗斗鱼幼鱼进行离散浸浴处理，最终对各种社会生殖行为进行分析，并对脑样本中的多巴胺、血浆样本中的性激素、皮质醇和葡萄糖等应激标志物进行分析。我们观察到，用50μg/L法倔唑处理的鱼中有91%发育为雄性。有趣的是，对这些雄性的生殖分析产生了两个亚组（A和B）。随后的社会行为分析表明，B亚组雄性表现出行为温顺的特点。此外，对脑组织中的多巴胺水平、血浆中的皮质醇和葡萄糖水平以及血浆中的性激素水平等应激标志物的评估显示，内分泌干扰介导的应激导致了这些雄性的行为改变。这些发现将有助于理解法倔唑介导的雄性化以及内分泌干扰后的行为改变。
