Biomaterial Database

Glutamine transport in normal and acidotic rat kidney mitochondria. 1994

A Atlante, and S Passarella, and G M Minervini, and E Quagliariello

Centro di Studio sui Mitocondri e Metabolismo Energetico, CNR, Bari, Italy.

Glutamine transport in both normal and acidotic rat kidney mitochondria was investigated using both isotopic techniques and by spectroscopic measurements in which glutamine metabolism was allowed to occur. Widely used criteria for demonstrating the occurrence of carrier-mediated transport were successfully applied in both cases. Three transport mechanisms were found to occur, namely glutamine uniport, active only during acidosis and glutamine/glutamate and glutamine/malate antiports, active in both normal and acidotic mitochondria. Efflux of glutamate, via a glutamate/OH- translocator, following glutamine uptake by mitochondria was experimentally ruled out. Glutamine uniport in acidotic mitochondria and glutamine/glutamate and glutamine/malate antiports in both normal and acidotic mitochondria were investigated in detail: differences found in Km and Vmax values, in pH and temperature dependence, and in the pattern of inhibitor sensitivity of glutamine transport demonstrated the existence of five different translocators whose activities were found to fit with the physiological requirements of renal ammoniogenesis.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008293	Malates	Derivatives of malic acid (the structural formula: (COO-)2CH2CHOH), including its salts and esters.
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
D005971	Glutamates	Derivatives of GLUTAMIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the 2-aminopentanedioic acid structure.	Glutamic Acid Derivatives,Glutamic Acids,Glutaminic Acids
D005973	Glutamine	A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.	D-Glutamine,L-Glutamine,D Glutamine,L Glutamine
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000138	Acidosis	A pathologic condition of acid accumulation or depletion of base in the body. The two main types are RESPIRATORY ACIDOSIS and metabolic acidosis, due to metabolic acid build up.	Metabolic Acidosis,Acidoses,Acidoses, Metabolic,Acidosis, Metabolic,Metabolic Acidoses
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