Ortega E, Rodriguez E, Ruiz E, Osorio C
Department of Biochemical and Molecular Biology, Faculty of Medicine, University of Granada, Spain.
Life Sci. 1990;46(6):391-5. doi: 10.1016/0024-3205(90)90081-2.
The hypothalamic pituitary ovarian axis in adult female rats with 131-I induced hypothyroidism was studied before and after triiodothyronine (T3) replacement. Forty days after 131-I, hypothyroid (H) rats showed irregular cycles with predominantly diestrous vaginal smears, atrophied and underweight ovaries, and decreased serum T3, T4, LH and estradiol (E2). T3 replacement restored normal cycles and ovary weight and increased serum E2 levels above control values, while LH levels remained below the limit of detection of the RIA. The GnRH stimulation test performed on the day that the rats exhibited diestrous vaginal smears elicited a greater increase in FSH than in LH in H rats and a greater increase in LH than in FSH in both H-T3 treated and control rats. The data suggest that the lack of thyroid hormones in adult female rats seems to produce a reversion of sexual hormones to a prepubertal pattern, while T3 treatment restored normal estrous cycles and ovarian function.
研究了131-I诱导甲状腺功能减退成年雌性大鼠在三碘甲状腺原氨酸（T3）替代治疗前后的下丘脑-垂体-卵巢轴。131-I处理40天后，甲状腺功能减退（H）大鼠出现周期不规则，主要为动情间期阴道涂片，卵巢萎缩且体重减轻，血清T3、T4、LH和雌二醇（E2）水平降低。T3替代治疗恢复了正常周期和卵巢重量，使血清E2水平升高至高于对照值，而LH水平仍低于放射免疫分析的检测限。在大鼠出现动情间期阴道涂片当天进行的GnRH刺激试验显示，H大鼠中FSH的增加幅度大于LH，而在H-T3治疗组和对照组大鼠中，LH的增加幅度大于FSH。数据表明，成年雌性大鼠甲状腺激素缺乏似乎使性激素水平恢复到青春期前模式，而T3治疗恢复了正常发情周期和卵巢功能。
