Neurochemical changes in the developing rat hippocampus during prolonged hypoglycemia.

Details

Serval ID
serval:BIB_E9CCF8A5690D
Type
Article: article from journal or magazin.
Collection
Publications
Title
Neurochemical changes in the developing rat hippocampus during prolonged hypoglycemia.
Journal
Journal of Neurochemistry
Author(s)
Rao R., Ennis K., Long J.D., Ugurbil K., Gruetter R., Tkac I.
ISSN
1471-4159[electronic], 0022-3042[linking]
Publication state
Published
Issued date
08/2010
Volume
114
Number
3
Pages
728-738
Language
english
Abstract
Hypoglycemia is common during development and is associated with the risk of neurodevelopmental deficits in human infants. The effects of hypoglycemia on the developing hippocampus are poorly understood. The sequential changes in energy substrates, amino acids and phosphocreatine were measured from the hippocampus during 180 min of insulin-induced hypoglycemia (blood glucose < 2.5 mmol/L) in 14-day-old rats using in vivo(1)H NMR spectroscopy. Hypoglycemia resulted in neuroglycopenia (brain glucose < 0.5 micromol/g). However, the phosphocreatine/creatine (PCr/Cr) ratio was maintained in the physiological range until approximately 150 min of hypoglycemia, indicating that energy supply was sufficient to meet the energy demands. Lactate concentration decreased soon after the onset of neuroglycopenia. Beyond 60 min, glutamine and glutamate became the major energy substrates. A precipitous decrease in the PCr/Cr ratio, indicative of impending energy failure occurred only after significant depletion of these amino acids. Once glutamate and glutamine were significantly exhausted, aspartate became the final energy source. N-acetylaspartate concentration remained unaltered, suggesting preservation of neuronal/mitochondrial integrity during hypoglycemia. Correction of hypoglycemia normalized the PCr/Cr ratio and partially restored the amino acids to pre-hypoglycemia levels. Compensatory neurochemical changes maintain energy homeostasis during prolonged hypoglycemia in the developing hippocampus.
Keywords
Animals, Animals, Newborn, Brain Chemistry/physiology, Chronic Disease, Energy Metabolism/physiology, Glucose/deficiency, Glutamic Acid/metabolism, Glutamine/metabolism, Glycolysis/physiology, Hippocampus/growth &amp, development, Hippocampus/metabolism, Homeostasis/physiology, Humans, Hypoglycemia/metabolism, Hypoglycemia/physiopathology, Infant Nutrition Disorders/metabolism, Infant Nutrition Disorders/physiopathology, Infant, Newborn, Lactic Acid/metabolism, Magnetic Resonance Spectroscopy, Neurons/metabolism, Oxidative Phosphorylation, Phosphocreatine/metabolism, Rats, Rats, Sprague-Dawley
Pubmed
Open Access
Yes
Create date
04/08/2010 15:28
Last modification date
20/08/2019 16:12
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