Acetate transport and utilization in the rat brain

Acetate, a glial-specific substrate, is an attractive alternative to glucose for the study of neuronal-glial interactions. The present study investigates the kinetics of acetate uptake and utilization in the rat brain in vivo during infusion of [2-¹³C]acetate using NMR spectroscopy. When plasma acet...

Full description

Saved in:
Bibliographic Details
Published in:Journal of neurochemistry 2009-05, Vol.109 (s1), p.46-54
Main Authors: Deelchand, Dinesh K, Shestov, Alexander A, Koski, Dee M, Uğurbil, Kâmil, Henry, Pierre-Gilles
Format: Article
Language:English
Subjects:
13C
acetate
Acetates - administration & dosage
Acetates - blood
Acetates - metabolism
Algorithms
Amino Acids - metabolism
Animals
Astrocytes - metabolism
Biochemistry
Biological Transport, Active - physiology
Biotransformation
Brain
Brain Chemistry - physiology
C
Citric Acid Cycle - physiology
Glutamic Acid - metabolism
Glutamine - metabolism
Infusions, Intravenous
Kinetics
LCModel
Magnetic Resonance Spectroscopy
Male
Neurology
NMR spectroscopy
nuclear magnetic resonance spectroscopy
Pyruvate Carboxylase - metabolism
Rats
Rats, Sprague-Dawley
Rodents
Substrates
transport
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Acetate, a glial-specific substrate, is an attractive alternative to glucose for the study of neuronal-glial interactions. The present study investigates the kinetics of acetate uptake and utilization in the rat brain in vivo during infusion of [2-¹³C]acetate using NMR spectroscopy. When plasma acetate concentration was increased, the rate of brain acetate utilization (CMRace) increased progressively and reached close to saturation for plasma acetate concentration > 2-3 mM, whereas brain acetate concentration continued to increase. The Michaelis-Menten constant for brain acetate utilization ( [graphic removed] = 0.01 ± 0.14 mM) was much smaller than for acetate transport through the blood-brain barrier (BBB) ( [graphic removed] = 4.18 ± 0.83 mM). The maximum transport capacity of acetate through the BBB ( [graphic removed] = 0.96 ± 0.18 μmol/g/min) was nearly twofold higher than the maximum rate of brain acetate utilization ( [graphic removed] = 0.50 ± 0.08 μmol/g/min). We conclude that, under our experimental conditions, brain acetate utilization is saturated when plasma acetate concentrations increase above 2-3 mM. At such high plasma acetate concentration, the rate-limiting step for glial acetate metabolism is not the BBB, but occurs after entry of acetate into the brain.
ISSN:0022-3042
1471-4159
DOI:10.1111/j.1471-4159.2009.05895.x