Campinho Marco A, Silva Nadia, Roman-Padilla Javier, Ponce Marian, Manchado Manuel, Power Deborah M
Comparative and Molecular Endocrinology Group, Marine Science Centre (CCMAR), Universidade do Algarve, Faro 8005-139, Portugal.
Comparative and Molecular Endocrinology Group, Marine Science Centre (CCMAR), Universidade do Algarve, Faro 8005-139, Portugal.
Mol Cell Endocrinol. 2015 Mar 15;404:16-25. doi: 10.1016/j.mce.2014.12.025. Epub 2015 Jan 6.
Anuran and flatfish metamorphosis are tightly regulated by thyroid hormones that are the necessary and sufficient factors that drive this developmental event. In the present study whole mount in situ hybridization (WISH) and quantitative PCR in sole are used to explore the central regulation of flatfish metamorphosis. Central regulation of the thyroid in vertebrates is mediated by the hypothalamus-pituitary-thyroid (HPT) axis. Teleosts diverge from other vertebrates as hypothalamic regulation in the HPT axis is proposed to be through hypothalamic inhibition although the regulatory factor remains enigmatic. The dynamics of the HPT axis during sole metamorphosis revealed integration between the activity of the thyrotrophes in the pituitary and the thyroid follicles. No evidence was found supporting a role for thyroid releasing hormone (trh) or corticotrophin releasing hormone (crh) in hypothalamic control of TH production during sole metamorphosis. Intriguingly the results of the present study suggest that neither hypothalamic trh nor crh expression changes during sole metamorphosis and raises questions about the role of these factors and the hypothalamus in regulation of thyrotrophs.
无尾两栖类动物和比目鱼的变态发育受到甲状腺激素的严格调控，甲状腺激素是驱动这一发育过程的必要且充分的因素。在本研究中，采用比目鱼的全胚胎原位杂交（WISH）和定量PCR技术来探究比目鱼变态发育的中枢调控机制。脊椎动物甲状腺的中枢调控是由下丘脑 - 垂体 - 甲状腺（HPT）轴介导的。硬骨鱼与其他脊椎动物不同，尽管调控因子尚不明确，但HPT轴的下丘脑调控被认为是通过下丘脑抑制来实现的。比目鱼变态发育过程中HPT轴的动态变化揭示了垂体促甲状腺细胞的活性与甲状腺滤泡之间的整合关系。在比目鱼变态发育过程中，未发现甲状腺释放激素（trh）或促肾上腺皮质激素释放激素（crh）在下丘脑控制甲状腺激素产生中发挥作用的证据。有趣的是，本研究结果表明，在比目鱼变态发育过程中，下丘脑trh和crh的表达均未发生变化，这引发了关于这些因素以及下丘脑在促甲状腺细胞调控中作用的疑问。
