Effect of hypoglycemia on brain glycogen metabolism in vivo.

Détails

ID Serval
serval:BIB_A4A66BAD48A3
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Effect of hypoglycemia on brain glycogen metabolism in vivo.
Périodique
Journal of Neuroscience Research
Auteur⸱e⸱s
Choi I.Y., Seaquist E.R., Gruetter R.
ISSN
0360-4012 (Print)
ISSN-L
0360-4012
Statut éditorial
Publié
Date de publication
04/2003
Volume
72
Numéro
1
Pages
25-32
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.Publication Status: ppublish. PDF type: Research Article
Résumé
The brain contains a small but significant amount of glycogen, which has long been considered to play an insignificant role in the brain. In this study, brain glycogen metabolism was measured using (13)C NMR spectroscopy at 9.4 T. Brain glycogen metabolism was modulated by hyperinsulinemia resulting in a net accumulation. The role of glycogen in maintaining brain function is unknown; one possibility is that it may serve as an endogenous glucose reservoir to protect the brain against severe hypoglycemia. To address this possibility, rats were subjected to insulin-induced moderate hypoglycemia and when the level of brain glucose approached zero, brain glycogen content began to decrease gradually, demonstrating utilization of this glucose reservoir. The brain glycogen signal never became undetectable, however, even during 2 hr of hypoglycemia. When plasma and brain glucose concentrations were restored, glycogen increased and the concentration exceeded the pre-hypoglycemic level by several-fold. The data suggest that brain glycogen can provide fuel for extended periods of time when glucose supply is inadequate. Furthermore, brain glycogen can rebound (super-compensate) after a single episode of hypoglycemia. We postulate that brain glycogen serves as an energy store during hypoglycemia and that it may participate in the creation of reduced physiological responses to hypoglycemia that are involved in a symptom often observed in patients with diabetes, hypoglycemia unawareness.
Mots-clé
Animals, Brain/drug effects, Brain/metabolism, Glycogen/metabolism, Hypoglycemia/chemically induced, Hypoglycemia/metabolism, Insulin/pharmacology, Magnetic Resonance Spectroscopy/methods, Male, Rats, Rats, Sprague-Dawley
Pubmed
Web of science
Création de la notice
04/08/2010 15:28
Dernière modification de la notice
20/08/2019 15:10
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