Ortega E, Osorio A, Ruiz E
Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Granada, Spain.
Biochem Mol Biol Int. 1996 Jul;39(4):853-60. doi: 10.1080/15216549600201951.
Hypothyroid female rats were treated with T4 and their 5'DI and 5'DII deiodinases were inhibited by PTU and IOP administration to determine whether the effect of T3 on reproductive function is a primary event at hypothalamo-pituitary levels or ovarian levels. Hypothyroid adult female rats were divided into four groups: Hypothyroid without treatment (H); hypothyroid treated with T4 (H-T4); hypothyroid treated with T4 plus propylthiouracil (H-T4-PTU), and hypothyroid treated with T4 plus iopanoic acid (H-T4-IOP). A group of euthyroid rats (E) was included as control. Estrous cycle, ovarian histological changes and serum estradiol and gonadotropin levels (basal and after GnRH) were searched in all groups. In view of our results and since sexual cycles and puberal pattern in gonadotropin secretion were restored after all treatments we can suggest: That T4 could have an intrinsic effect on reproductive function in adult hypothyroid female rats or that another compensatory T3 mechanism unaffected by IOP could exist. The present report points out that the effect of T3 on reproductive function could be a primary event at hypothalamopituitary levels although an effect at ovarian levels could not be excluded.
对甲状腺功能减退的雌性大鼠给予 T4 治疗，并通过给予丙硫氧嘧啶（PTU）和碘番酸（IOP）抑制其 5'-脱碘酶 I（5'DI）和 5'-脱碘酶 II（5'DII），以确定 T3 对生殖功能的影响是在下丘脑-垂体水平还是卵巢水平上的原发性事件。将成年甲状腺功能减退的雌性大鼠分为四组：未治疗的甲状腺功能减退组（H）；用 T4 治疗的甲状腺功能减退组（H-T4）；用 T4 加丙硫氧嘧啶治疗的甲状腺功能减退组（H-T4-PTU），以及用 T4 加碘番酸治疗的甲状腺功能减退组（H-T4-IOP）。纳入一组甲状腺功能正常的大鼠（E）作为对照。研究了所有组的发情周期、卵巢组织学变化以及血清雌二醇和促性腺激素水平（基础水平和 GnRH 刺激后）。鉴于我们的研究结果，并且由于所有治疗后性腺激素分泌的性周期和青春期模式均得以恢复，我们可以提出：T4 可能对成年甲状腺功能减退雌性大鼠的生殖功能具有内在影响，或者可能存在另一种不受 IOP 影响的代偿性 T3 机制。本报告指出，T3 对生殖功能的影响可能是下丘脑-垂体水平上的原发性事件，尽管不能排除其在卵巢水平上的作用。
