Biomaterial Database

Acute thyroid hormone withdrawal rapidly increases the thyrotropin beta and alpha-subunit messenger ribonucleic acids in mouse thyrotropic tumors. 1986

D S Ross, and M F Ellis, and E C Ridgway

We have abruptly discontinued T3 administration to hypothyroid mice bearing thyrotropic tumors and measured increases in tumor steady state TSH subunit mRNA levels with time. Hypothyroid mice bearing the thyrotropic tumor TtT97 were injected daily with T3 (10 micrograms/100 g BW, ip, daily) for 10 days. Groups of mice (n = 3) were killed on the day of the last T3 injection (day 0) and 1, 2, 3, or 5 days after stopping T3 treatment. Plasma T3 concentrations fell to subnormal values between days 1 and 2 after stopping T3 treatment. Plasma TSH and total TSH subunit concentrations were 3% of untreated hypothyroid control concentrations on day 0, and rose 4-fold between days 1 and 2 and 20-fold by day 5 (P less than 0.01). Plasma total alpha-subunit concentrations were 28% of untreated hypothyroid control concentrations on day 0, rose to 158% of baseline values by day 2, and rose 3-fold by day 5 (P less than 0.001). Tumor TSH beta and alpha-subunit mRNA levels were 5% and 52% (P less than 0.01) of hypothyroid control levels on day 0. TSH beta mRNA levels rose nearly 9-fold between days 1 and 2 (P less than 0.01). alpha-Subunit mRNA levels rose to 135% of initial values by day 2 and to 144% of initial values by day 3 (P less than 0.05). Changes in tumor TSH subunit mRNA levels paralleled changes in plasma subunit glycoprotein concentrations. Increases in tumor subunit mRNA levels after abruptly stopping T3 treatment occurred rapidly, predominantly between 24-48 h after stopping T3, and TSH beta mRNA was considerably more responsive than alpha-subunit mRNA.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006706	Homeostasis	The processes whereby the internal environment of an organism tends to remain balanced and stable.	Autoregulation
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012333	RNA, Messenger	RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.	Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated
D013963	Thyroid Hormones	Natural hormones secreted by the THYROID GLAND, such as THYROXINE, and their synthetic analogs.	Thyroid Hormone,Hormone, Thyroid,Hormones, Thyroid
D013964	Thyroid Neoplasms	Tumors or cancer of the THYROID GLAND.	Cancer of Thyroid,Thyroid Cancer,Cancer of the Thyroid,Neoplasms, Thyroid,Thyroid Adenoma,Thyroid Carcinoma,Adenoma, Thyroid,Adenomas, Thyroid,Cancer, Thyroid,Cancers, Thyroid,Carcinoma, Thyroid,Carcinomas, Thyroid,Neoplasm, Thyroid,Thyroid Adenomas,Thyroid Cancers,Thyroid Carcinomas,Thyroid Neoplasm
D013972	Thyrotropin	A glycoprotein hormone secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Thyrotropin stimulates THYROID GLAND by increasing the iodide transport, synthesis and release of thyroid hormones (THYROXINE and TRIIODOTHYRONINE). Thyrotropin consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the pituitary glycoprotein hormones (TSH; LUTEINIZING HORMONE and FSH), but the beta subunit is unique and confers its biological specificity.	Thyroid-Stimulating Hormone,TSH (Thyroid Stimulating Hormone),Thyreotropin,Thyrotrophin,Hormone, Thyroid-Stimulating,Thyroid Stimulating Hormone
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus