Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada.
Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada; Aquaculture Program, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil; Department of Morphology, Reproductive and Molecular Biology Group, São Paulo State University, Botucatu, São Paulo, Brazil.
Mol Cell Endocrinol. 2019 Jul 15;492:110440. doi: 10.1016/j.mce.2019.04.020. Epub 2019 Apr 29.
Control of testicular development is multifactorial and involves a number of hypothalamic, hypophyseal and peripheral hormones. Here, we investigated direct action of zebrafish gonadotropin-inhibitory hormone (zGnih) which is expressed in the testis, on spermatogenesis in zebrafish, in vitro. Treatment with zGnih at the lower doses (10 and 100 nM) inhibited gonadotropin-induced spermatids/spermatozoa (SPD/SPZ) production. However, at the highest dose (1000 nM), zGnih increased basal number of SPD/SPZ and showed paradoxical effect. The effects of zGnih on testosterone and SPD/SPZ production was blocked in the presence of androgen receptor antagonist, flutamide (FLU). A number of transcripts were also measured to better understand zGnih mechanisms of action on zebrafish spermatogenesis. Our results provide strong support for the hypothesis that locally produced zGnih is a component of the complex multifactorial system that regulates testicular development and function in adult zebrafish, in part, by changes in testicular steroidogenesis and regulation of gonadotropin-induced response.
睾丸发育的调控是多因素的，涉及到下丘脑、垂体和外周激素的多种激素。在这里，我们研究了在睾丸中表达的斑马鱼促性腺激素抑制激素（zGnih）对斑马鱼体外精子发生的直接作用。用较低剂量（10 和 100nM）的 zGnih 处理抑制了促性腺激素诱导的精母细胞/精子（SPD/SPZ）的产生。然而，在最高剂量（1000nM）时，zGnih 增加了 SPD/SPZ 的基础数量，并表现出反常的效果。在存在雄激素受体拮抗剂氟他胺（FLU）的情况下，zGnih 对睾酮和 SPD/SPZ 产生的影响被阻断。还测量了许多转录本，以更好地了解 zGnih 对斑马鱼精子发生的作用机制。我们的结果为局部产生的 zGnih 是调节成年斑马鱼睾丸发育和功能的复杂多因素系统的一个组成部分的假设提供了强有力的支持，部分原因是睾丸类固醇生成和促性腺激素诱导反应的调节发生了变化。
