Biomaterial Database

Metabolism of D- and L-[(13)C]alanine in rat liver detected by (1)H and (13)C NMR spectroscopy in vivo and in vitro. 2000

A Dölle

Abteilung Biophysikalische Chemie, Biozentrum der Universität Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland. doelle@rwth-aachen.de

Alanine is the major amino acid utilized by the liver for gluconeogenesis under normal conditions. The metabolism of alanine in rat liver was investigated by means of (1)H and (13)C NMR spectroscopic studies in vivo and in vitro after infusion of L- and D-alanine labelled with (13)C at the carboxyl and methyl group into normal, fasted rats. Valuable information about different metabolic pathways of alanine in rat liver and their regulation under the conditions of gluconeogenesis were obtained. The enrichment of the alanine pool by the infusate was estimated to be 11% for L-alanine and 70% for D-alanine. After infusion of labelled D-alanines, the metabolic pathway via D-amino acid oxidase was observed. The labelled alanines entered the tricarboxylic acid cycle mainly via pyruvate carboxylase; the ratio of pyruvate dehydrogenase activity to that of pyruvate carboxylase is about 28%. The ratio of flux from phosphoenolpyruvate (PEP) through phosphoenolpyruvate kinase as compared with the flux from PEP to glucose was approximately 42%. From the labelling pattern of glucose it was concluded that the pentose phosphate cycle was active under the experimental conditions.

UI	MeSH Term	Description	Entries
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
D008297	Male		Males
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009682	Magnetic Resonance Spectroscopy	Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).	In Vivo NMR Spectroscopy,MR Spectroscopy,Magnetic Resonance,NMR Spectroscopy,NMR Spectroscopy, In Vivo,Nuclear Magnetic Resonance,Spectroscopy, Magnetic Resonance,Spectroscopy, NMR,Spectroscopy, Nuclear Magnetic Resonance,Magnetic Resonance Spectroscopies,Magnetic Resonance, Nuclear,NMR Spectroscopies,Resonance Spectroscopy, Magnetic,Resonance, Magnetic,Resonance, Nuclear Magnetic,Spectroscopies, NMR,Spectroscopy, MR
D002247	Carbon Isotopes	Stable carbon atoms that have the same atomic number as the element carbon but differ in atomic weight. C-13 is a stable carbon isotope.	Carbon Isotope,Isotope, Carbon,Isotopes, Carbon
D005943	Gluconeogenesis	Biosynthesis of GLUCOSE from nonhexose or non-carbohydrate precursors, such as LACTATE; PYRUVATE; ALANINE; and GLYCEROL.
D005947	Glucose	A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.	Dextrose,Anhydrous Dextrose,D-Glucose,Glucose Monohydrate,Glucose, (DL)-Isomer,Glucose, (alpha-D)-Isomer,Glucose, (beta-D)-Isomer,D Glucose,Dextrose, Anhydrous,Monohydrate, Glucose
D006859	Hydrogen	The first chemical element in the periodic table with atomic symbol H, and atomic number 1. Protium (atomic weight 1) is by far the most common hydrogen isotope. Hydrogen also exists as the stable isotope DEUTERIUM (atomic weight 2) and the radioactive isotope TRITIUM (atomic weight 3). Hydrogen forms into a diatomic molecule at room temperature and appears as a highly flammable colorless and odorless gas.	Protium,Hydrogen-1
D000409	Alanine	A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.	Abufène,Alanine, L-Isomer,L-Alanine,Alanine, L Isomer,L Alanine,L-Isomer Alanine
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino