Suppression of hypothalamic deiodinase type II activity blunts TRH mRNA decline during fasting

被引：41

作者：

Coppola, A

Hughes, J

Esposito, E

Schiavo, L

Meli, R

Diano, S

机构：

[1] Yale Univ, Sch Med, Dept Obstet Gynecol & Reprod Sci, New Haven, CT 06520 USA

[2] Univ Naples Federico II, Dept Expt Pharmacol, I-80131 Naples, Italy

[3] Yale Univ, Sch Med, Dept Neurobiol, New Haven, CT 06520 USA

来源：

FEBS LETTERS | 2005年 / 579卷 / 21期

关键词：

hypothalamus; deiodinase type II; fasting; enzymatic activity; iopanoic acid;

D O I：

10.1016/j.febslet.2005.07.035

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Fasting is characterized by disrupted thyroid feedback, with suppressed levels of thyroid hormones and paraventricular thyrotropin releasing hormone (TRH). We found that third ventricle administration of the deiodinase inhibitor, iopanoic acid, dose-dependently reduced deiodinase type II (DII) activity selectively in the hypothalamus. This suppression of DII by iopanoic acid during fasting prevented elevated DII activity and blunted the decline in hypothalamic TRH mRNA levels. Because fasting-induced elevation in hypothalamic DII activity is paralleled by increased hypothalamic T3 concentration, our study suggests that T3 formation by DII in the hypothalamus is the cause of disrupted thyroid feedback during fasting. (c) 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

引用

页码：4654 / 4658

页数：5

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