MacLatchy D L, Eales J G
Department of Zoology, University of Manitoba, Winnipeg, Canada.
Gen Comp Endocrinol. 1990 May;78(2):164-72. doi: 10.1016/0016-6480(90)90002-4.
Intraperitoneal injection of rainbow trout (Salmo gairdneri) with 0.4 microgram/g of human growth hormone (hGH) increased plasma levels of 3,5,3'-triiodo-L-thyronine (T3) and Vmax of the hepatic microsomal 5'-monodeiodinase enzyme (5'D) that converts thyroxine (T4) to T3, with no effect on Km or plasma T4 levels. A dose of 0.4 microgram hGH/g increased both plasma T3 and Vmax as early as 8 hr postinjection (pi). Maximal levels for both parameters occurred at 24 hr pi and significant stimulation was sustained to 48 hr pi. In trout injected with hGH over a dose range of 0.1-1.0 microgram/g and sampled at 24 hr pi, both Vmax and plasma T3 increased in a dose-dependent manner. It is concluded that the increase in the level of functional hepatic 5'D may contribute to the rapid hGH-induced elevation in plasma T3.
给虹鳟（萨氏虹鳟）腹腔注射0.4微克/克的人生长激素（hGH），可提高血浆中3,5,3'-三碘甲腺原氨酸（T3）的水平以及肝脏微粒体5'-单脱碘酶（5'D）的Vmax，该酶可将甲状腺素（T4）转化为T3，而对Km或血浆T4水平无影响。0.4微克hGH/克的剂量在注射后（pi）8小时就可提高血浆T3和Vmax。这两个参数的最高水平出现在注射后24小时，显著刺激持续到注射后48小时。在注射剂量范围为0.1 - 1.0微克/克hGH并在注射后24小时取样的虹鳟中，Vmax和血浆T3均呈剂量依赖性增加。结论是，功能性肝脏5'D水平的升高可能有助于hGH诱导的血浆T3快速升高。
