Alteration of hypothalamic glucose and lactate sensing in 48h hyperglycemic rats.

Détails

ID Serval
serval:BIB_9356DD874D32
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Alteration of hypothalamic glucose and lactate sensing in 48h hyperglycemic rats.
Périodique
Neuroscience Letters
Auteur⸱e⸱s
Allard C., Carneiro L., Collins S.C., Chrétien C., Grall S., Pénicaud L., Leloup C.
ISSN
1872-7972 (Electronic)
ISSN-L
0304-3940
Statut éditorial
Publié
Date de publication
2013
Volume
534
Pages
75-79
Langue
anglais
Résumé
Hypothalamic detection of nutrients is involved in the control of energy metabolism and is altered in metabolic disorders. Although hypothalamic detection of blood lactate lowers hepatic glucose production and food intake, it is unknown whether it also modulates insulin secretion. To address this, a lactate injection via the right carotid artery (cephalad) was performed in Wistar rats. This triggered a transient increase in insulin secretion. Rats made hyperglycemic for 48h exhibited prolonged insulin secretion in response to a glucose injection via the carotid artery, but lactate injection induced two types of responses: half of the HG rats showed no difference compared to controls and the other half had markedly decreased insulin secretion. Astroglial monocarboxylates transporters MCT1 and MCT4 isoforms transfer lactate from blood to astrocytes and release lactate to the extracellular space, whilst the neuronal MCT2 isoform permits neuronal lactate uptake. We found that astroglial MCT1 and MCT4, and neuronal MCT2 protein levels in the medio-basal hypothalamus (MBH) were not modified by 48h-hyperglycemia. Together, these results indicate that hypothalamic sensing of circulating lactate triggers insulin secretion. Both glucose and lactate sensing are altered in a model of hyperglycemia, without alteration of MBH MCTs protein levels.
Mots-clé
Animals, Glucose/metabolism, Glucose/pharmacology, Hyperglycemia/metabolism, Hypothalamus/blood supply, Hypothalamus/metabolism, Insulin/secretion, Lactic Acid/blood, Lactic Acid/pharmacology, Male, Monocarboxylic Acid Transporters/metabolism, Muscle Proteins/metabolism, Rats, Rats, Wistar, Symporters/metabolism, Time Factors
Pubmed
Web of science
Création de la notice
20/10/2015 13:21
Dernière modification de la notice
20/08/2019 14:56
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