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PubMed · 7545100

Hypothalamic nitric oxide synthase gene expression is regulated by thyroid hormones.

Y Ueta·A Levy·H S Chowdrey·S L Lightman
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Abstract

We investigated the effects of thyroid status on nitric oxide synthase (NOS) gene expression in the rat hypothalamic paraventricular (PVN) and supraoptic nuclei (SON). Propylthiouracil (PTU)-induced hypothyroidism in male rats produced a highly significant reduction in NOS gene transcripts in the PVN and SON, as assessed by quantitative in situ hybridization histochemistry with a specific oligodeoxynucleotide probe. The addition of T3 (40 micrograms/kg) to the PTU-containing diet completely prevented the reduction in NOS transcripts. Hyperthyroidism, induced by adding 160 micrograms/kg T3 to the food, more than doubled the prevalence of NOS transcripts in the PVN and SON after a similar time. Up-regulation of NOS gene transcripts induced by the osmotic stimulus of chronic salt loading was markedly attenuated by PTU-induced hypothyroidism. These results demonstrate a major effect of thyroid status on regulation of NOS gene expression in the hypothalamus.

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Amino Acid OxidoreductasesAnimalsBase SequenceGene Expression Regulation, EnzymologicHypothalamusMaleMolecular Sequence DataNitric Oxide SynthasePropylthiouracilRNA, MessengerRatsRats, Sprague-DawleyThyroid HormonesThyrotropinThyrotropin-Releasing HormoneJournal ArticleResearch Support, Non-U.S. Gov't

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Y Ueta, A Levy, H S Chowdrey, S L Lightman. 1995. Hypothalamic nitric oxide synthase gene expression is regulated by thyroid hormones.. https://doi.org/10.1210/endo.136.10.7545100

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