Biomaterial Database

Testosterone stimulation of mitochondrial aspartate aminotransferase levels and biosynthesis in rat ventral prostate. 1987

R B Franklin, and B I Kukoyi, and V Akuffo, and L C Costello

Department of Physiology, Dental School, University of Maryland, Baltimore 21201.

The effects of testosterone on mitochondrial aspartate aminotransferase (mAAT) synthesis in rat ventral prostate was investigated. Procedures for the isolation, purification and characterization of AAT isozymes were developed and described. Purified mAAT preparations contained no demonstrable contaminating proteins. Prostatic mAAT was characterized as a cationic protein with an estimated mol. wt of 120,000. Cytoplasmic AAT (cAAT) isozyme was identified as an anionic protein with an estimated mol. wt of 132,000. A cytosolic cationic isozyme, similar to mAAT, was also identified as pre-mAAT. Testosterone administration to castrated rats resulted in significant increases in leucine incorporation into mAAT, in the level of mAAT, and in mAAT activity. These effects of testosterone were observed within 2 h of administration. Conversely, testosterone administration had none of these effects on cAAT or on non-AAT protein pool. Testosterone treatment did appear to increase leucine incorporation into pre-mAAT. Testosterone treatment in organ cultures and in prostate epithelial cell cultures resulted in the same stimulatory effects on mAAT as observed in the in vivo studies. The hormone was effective at the physiological concentration of 2 X 10(-9) M. These results indicated that testosterone has a rapid and specific effect on the biosynthesis of mAAT. This continues to support our proposal that testosterone regulates prostate citrate production via a stimulatory effect on mAAT which results in increased mitochondrial synthesis of citrate from aspartate.

UI	MeSH Term	Description	Entries
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D007700	Kinetics	The rate dynamics in chemical or physical systems.
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
D009924	Organ Culture Techniques	A technique for maintenance or growth of animal organs in vitro. It refers to three-dimensional cultures of undisaggregated tissue retaining some or all of the histological features of the tissue in vivo. (Freshney, Culture of Animal Cells, 3d ed, p1)	Organ Culture,Culture Technique, Organ,Culture Techniques, Organ,Organ Culture Technique,Organ Cultures
D011467	Prostate	A gland in males that surrounds the neck of the URINARY BLADDER and the URETHRA. It secretes a substance that liquefies coagulated semen. It is situated in the pelvic cavity behind the lower part of the PUBIC SYMPHYSIS, above the deep layer of the triangular ligament, and rests upon the RECTUM.	Prostates
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
D004790	Enzyme Induction	An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.	Induction, Enzyme
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
D001219	Aspartate Aminotransferases	Enzymes of the transferase class that catalyze the conversion of L-aspartate and 2-ketoglutarate to oxaloacetate and L-glutamate. EC 2.6.1.1.	Aspartate Aminotransferase,Aspartate Transaminase,Glutamic-Oxaloacetic Transaminase,SGOT,Aspartate Apoaminotransferase,Glutamate-Aspartate Transaminase,L-Aspartate-2-Oxoglutarate Aminotransferase,Serum Glutamic-Oxaloacetic Transaminase,Aminotransferase, Aspartate,Aminotransferase, L-Aspartate-2-Oxoglutarate,Aminotransferases, Aspartate,Apoaminotransferase, Aspartate,Glutamate Aspartate Transaminase,Glutamic Oxaloacetic Transaminase,Glutamic-Oxaloacetic Transaminase, Serum,L Aspartate 2 Oxoglutarate Aminotransferase,Serum Glutamic Oxaloacetic Transaminase,Transaminase, Aspartate,Transaminase, Glutamate-Aspartate,Transaminase, Glutamic-Oxaloacetic,Transaminase, Serum Glutamic-Oxaloacetic