Biomaterial Database

Age-related changes in rat hepatic and renal thyroid hormone-sensitive enzymes--different responses to acute and chronic L-triiodothyronine stimulation. 1988

K Sawada, and B C Hummel, and P G Walfish

Thyroid Research Laboratory, Mount Sinai Institute, Ontario, Canada.

Using young (5-6 weeks) and adult (12-14 months) male Sprague-Dawley rats, the responses of hepatic and renal cytosolic malic enzymes (ME) and mitochondrial alpha-glycerophosphate dehydrogenase (alpha-GPDH), have been assessed following acute and chronic L-triiodothyronine (T3) administration. In control (untreated) animals a significant reduction of renal ME as well as hepatic and renal alpha-GPDH activity with increased age were observed but renal ME activity was not age-related. Following acute T3 stimulation (200 micrograms T3/100 g body wt single injection), the levels of hepatic ME and alpha-GPDH as well as renal alpha-GPDH but not renal ME remained lower in the adult than in the younger group. After chronic T3 stimulation (15 micrograms T3/100 g body wt for 7 days) or 200 micrograms T3/100 g body wt for 4 days), the enzyme levels remained significantly lower in older animals for hepatic ME but were no longer different for hepatic and renal alpha-GPDH, while renal ME, which was not altered with age, had values that were the same as in the younger group. These studies have demonstrated that age-related changes in hepatic and renal T3-sensitive enzymes could not be attributed solely to T3 occupancy of nuclear receptor binding sites, but may be influenced by other factors depending upon the specific tissues and subcellular T3-sensitive enzymes being assessed.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008291	Malate Dehydrogenase	An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 1.1.1.37.	Malic Dehydrogenase,NAD-Malate Dehydrogenase,Dehydrogenase, Malate,Dehydrogenase, Malic,Dehydrogenase, NAD-Malate,NAD Malate Dehydrogenase
D008297	Male		Males
D008928	Mitochondria	Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Mitochondrial Contraction,Mitochondrion,Contraction, Mitochondrial,Contractions, Mitochondrial,Mitochondrial Contractions
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
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
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D005993	Glycerolphosphate Dehydrogenase		Alpha-Glycerophosphate Dehydrogenase,Glycerol-3-Phosphate Dehydrogenase,Glycerophosphate Dehydrogenase,Glycerophosphate Oxidase,Alpha Glycerophosphate Dehydrogenase,Dehydrogenase, Alpha-Glycerophosphate,Dehydrogenase, Glycerol-3-Phosphate,Dehydrogenase, Glycerolphosphate,Dehydrogenase, Glycerophosphate,Glycerol 3 Phosphate Dehydrogenase,Oxidase, Glycerophosphate
D000367	Age Factors	Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.	Age Reporting,Age Factor,Factor, Age,Factors, Age