Biomaterial Database

Pituitary nuclear triiodothyronine receptors during development in the rat. 1983

P Coulombe, and J Ruel, and R Faure, and J H Dussault

Studies were undertaken to measure the pituitary nuclear triiodothyronine (T3) binding capacity (BC) during development in the rat. BC was measured in 0.4 M NaCl-solubilized receptors in 5-, 14-, 20-, 27-, 30-, 40-, 50-day-old rats and in adult animals. Results indicate that BC is lower in 5-day-old rats than in adult animals (0.397 +/- 0.02 vs. 0.797 +/- 0.06 pmol T3/mg protein) (mean +/- SE) (P less than 0.01). Hypothyroidism, induced during the neonatal period or in the adult animal, results in a significant decrease in BC (P less than 0.01) when compared with control rats. However, treatment of hypothyroid animals with T3 (0.4 micrograms/100 g body wt) for a period of 7-14 days significantly increased BC as compared with hypothyroid rats without apparent changes in Ka. The relative affinities of various thyroid hormone analogues for the nuclear receptor were also measured in the adult animal. The affinities of these analogues are in the following order: TRIAC greater than L-T3 greater than D-T3 greater than L-T4 greater than D-T4 greater than DIMIT greater than L-T2 greater than rT3. The present findings demonstrate the presence of high affinity nuclear T3 binding sites in the pituitary of neonatal rat and could thus account for the effects of thyroid hormones on GH synthesis and TSH secretion observed in these animals.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008297	Male		Males
D010902	Pituitary Gland	A small, unpaired gland situated in the SELLA TURCICA. It is connected to the HYPOTHALAMUS by a short stalk which is called the INFUNDIBULUM.	Hypophysis,Hypothalamus, Infundibular,Infundibular Stalk,Infundibular Stem,Infundibulum (Hypophysis),Infundibulum, Hypophyseal,Pituitary Stalk,Hypophyseal Infundibulum,Hypophyseal Stalk,Hypophysis Cerebri,Infundibulum,Cerebri, Hypophysis,Cerebrus, Hypophysis,Gland, Pituitary,Glands, Pituitary,Hypophyseal Stalks,Hypophyses,Hypophysis Cerebrus,Infundibular Hypothalamus,Infundibular Stalks,Infundibulums,Pituitary Glands,Pituitary Stalks,Stalk, Hypophyseal,Stalk, Infundibular,Stalks, Hypophyseal,Stalks, Infundibular
D011441	Propylthiouracil	A thiourea antithyroid agent. Propythiouracil inhibits the synthesis of thyroxine and inhibits the peripheral conversion of throxine to tri-iodothyronine. It is used in the treatment of hyperthyroidism. (From Martindale, The Extra Pharmacopeoia, 30th ed, p534)	6-Propyl-2-Thiouracil,6 Propyl 2 Thiouracil
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D011988	Receptors, Thyroid Hormone	Specific high affinity binding proteins for THYROID HORMONES in target cells. They are usually found in the nucleus and regulate DNA transcription. These receptors are activated by hormones that leads to transcription, cell differentiation, and growth suppression. Thyroid hormone receptors are encoded by two genes (GENES, ERBA): erbA-alpha and erbA-beta for alpha and beta thyroid hormone receptors, respectively.	Diiodotyrosine Receptors,Receptors, Diiodotyrosine,Receptors, Thyroxine,Receptors, Triiodothyronine,T3 Receptors,T4 Receptors,Thyroid Hormone Receptors,Thyroxine Receptors,Triiodothyronine Receptors,DIT Receptors,Diiodotyrosine Receptor,MIT Receptors,Monoiodotyrosine Receptors,Receptors, DIT,Receptors, MIT,Receptors, Monoiodotyrosine,Receptors, T3,Receptors, T4,T3 Receptor,T4 Receptor,Thyroid Hormone Receptor,Thyroxine Receptor
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D005260	Female		Females
D000375	Aging	The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.	Senescence,Aging, Biological,Biological Aging