Glucose and amino acid metabolism in rat brain during sustained hypoglycemia

Journal Article · Fri Apr 01 04:00:00 EST 1983 · Neurochem. Res.; (United States)

DOI:https://doi.org/10.1007/BF00965097· OSTI ID:5505137

Wong, K L; Tyce, G M

The metabolism of glucose in brains during sustained hypoglycemia was studied. (U-/sup 14/C)Glucose (20 microCi) was injected into control rats, and into rats at 2.5 hr after a bolus injection of 2 units of insulin followed by a continuous infusion of 0.2 units/100 g rat/hr. This regimen of insulin injection was found to result in steady-state plasma glucose levels between 2.5 and 3.5 mumol per ml. In the brains of control rats carbon was transferred rapidly from glucose to glutamate, glutamine, gamma-aminobutyric acid and aspartate and this carbon was retained in the amino acids for at least 60 min. In the brains of hypoglycemic rats, the conversion of carbon from glucose to amino acids was increased in the first 15 min after injection. After 15 min, the specific activity of the amino acids decreased in insulin-treated rats but not in the controls. The concentrations of alanine, glutamate, and gamma-amino-butyric acid decreased, and the concentration of aspartate increased, in the brains of the hypoglycemic rats. The concentration of pyridoxal-5'-phosphate, a cofactor in many of the reactions whereby these amino acids are formed from tricarboxylic acid cycle intermediates, was less in the insulin-treated rats than in the controls. These data provide evidence that glutamate, glutamine, aspartate, and GABA can serve as energy sources in brain during insulin-induced hypoglycemia.

• Research Organization: Faculty of Medicine, University of Calgary, Canada
• OSTI ID: 5505137
• Journal Information: Neurochem. Res.; (United States), Journal Name: Neurochem. Res.; (United States) Journal Issue: 4 Vol. 8:4; ISSN NERED
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALANINES
ALDEHYDES
AMIDES
AMINO ACIDS
AMINOBUTYRIC ACID
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BLOOD CHEMISTRY
BODY
BRAIN
CARBOHYDRATES
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM
DRUGS
GLUCOSE
GLUTAMINE
HEXOSES
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
METABOLISM
MONOSACCHARIDES
NERVOUS SYSTEM
NEUROREGULATORS
NUTRITIONAL DEFICIENCY
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
RATS
RODENTS
SACCHARIDES
TRACER TECHNIQUES
VERTEBRATES