Thyroid Hormones Regulate Levels of Thyrotropin-releasing-hormone MRNA in the Paraventricular Nucleus
Overview
Authors
Affiliations
Cellular levels of messenger RNA encoding thyrotropin-releasing hormone (TRH) were measured in the paraventricular nucleus of the hypothalamus and the reticular nucleus of the thalamus in male rats after chemical thyroidectomy and thyroid hormone replacement. TRH mRNA levels were measured by quantitative in situ hybridization histochemistry using a 35S-labeled synthetic 48-base oligodeoxynucleotide probe and quantitative autoradiography. Chemical thyroidectomy, produced by the administration of 6-(n-propyl)-2-thiouracil (PrSur), reduced plasma thyroxine below detection limits and significantly increased TRH mRNA in the paraventricular nucleus. Treatment with exogenous L-triiodothyronine (T3) reduced TRH mRNA to the same level in both hypothyroid and euthyroid animals. Neither PrSur treatment nor T3 replacement influenced TRH mRNA levels in the reticular nucleus of the thalamus. Blot hybridization analysis of electrophoretically fractionated total RNA from pituitaries of these animals indicated that thyrotropin-beta mRNA levels were elevated after thyroidectomy and reduced by T3 treatment, showing that the pituitary-thyroid axis was indeed stimulated by PrSur treatment. These results suggest that thyroid hormones are involved, either directly or indirectly, in regulating the biosynthesis of TRH in the thyrotropic center of the hypothalamus.
ASIC1a affects hypothalamic signaling and regulates the daily rhythm of body temperature in mice.
Peng Z, Ziros P, Martini T, Liao X, Stoop R, Refetoff S Commun Biol. 2023; 6(1):857.
PMID: 37591947 PMC: 10435469. DOI: 10.1038/s42003-023-05221-2.
Reduced pituitary size in subjects with mutations in the THRB gene and thyroid hormone resistance.
Heldmann M, Chatterjee K, Moran C, Rogge B, Steinhardt J, Wagner-Altendorf T Endocr Connect. 2021; 11(1).
PMID: 34860176 PMC: 8789019. DOI: 10.1530/EC-21-0473.
Role of hypothyroidism and associated pathways in pregnancy and infertility: Clinical insights.
Koyyada A, Orsu P Tzu Chi Med J. 2020; 32(4):312-317.
PMID: 33163375 PMC: 7605301. DOI: 10.4103/tcmj.tcmj_255_19.
Tanycytes and the Control of Thyrotropin-Releasing Hormone Flux Into Portal Capillaries.
Rodriguez-Rodriguez A, Lazcano I, Sanchez-Jaramillo E, Uribe R, Jaimes-Hoy L, Joseph-Bravo P Front Endocrinol (Lausanne). 2019; 10:401.
PMID: 31293518 PMC: 6603095. DOI: 10.3389/fendo.2019.00401.
Bansal R, Zoeller R Endocrinology. 2019; 160(8):1771-1785.
PMID: 31135896 PMC: 6937519. DOI: 10.1210/en.2019-00121.