Watanabe K, Takekoshi S, Kakudo K
Department of Pathology, School of Medicine, Tokai University, Kanagawa, Japan.
Calcif Tissue Int. 1992;51 Suppl 1:S27-9. doi: 10.1007/BF02180246.
Ipriflavone is known to stimulate calcitonin (CT) secretion from the thyroid glands of female animals, but the exact mechanism of this action remains unknown. In the present study, an increase of CT production in thyroid C cells of female rats, but not of male rats, was proven immunohistochemically. Furthermore, the parallel increase of CT mRNA in those thyroid glands was confirmed by Northern blot analysis. These results proved that ipriflavone stimulates not only CT secretion but also CT synthesis in thyroid C cells and that the changes were gender dependent (greater in females). In order to investigate the effect of estrogen on the ipriflavone-induced increase of CT in female rat thyroid gland, CT and CT mRNA in the thyroid glands of untreated, ovariectomized, and estrone-treated (postovariectomy) rats were examined by both immunohistochemistry and Northern blot technique. Serum levels of CT and calcium were also examined. Against expectation, estrone failed to produce any significant effect on the ability of ipriflavone to induce CT synthesis and secretion.
已知依普黄酮可刺激雌性动物甲状腺分泌降钙素（CT），但这一作用的确切机制尚不清楚。在本研究中，免疫组织化学证实雌性大鼠而非雄性大鼠的甲状腺C细胞中CT生成增加。此外，通过Northern印迹分析证实了这些甲状腺中CT mRNA的平行增加。这些结果证明依普黄酮不仅刺激甲状腺C细胞中CT的分泌，还刺激其合成，且这些变化具有性别依赖性（雌性更明显）。为了研究雌激素对依普黄酮诱导的雌性大鼠甲状腺CT增加的影响，采用免疫组织化学和Northern印迹技术检测了未处理、去卵巢和雌酮处理（去卵巢后）大鼠甲状腺中的CT和CT mRNA。还检测了血清CT和钙水平。出乎意料的是，雌酮对依普黄酮诱导CT合成和分泌的能力未产生任何显著影响。
