Orexin a stimulates hypothalamic-pituitary-adrenal (HPA) axis function, but not food intake, in the absence of full hypothalamic NPY-ergic activity

Détails

ID Serval
serval:BIB_7A0088159779
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Orexin a stimulates hypothalamic-pituitary-adrenal (HPA) axis function, but not food intake, in the absence of full hypothalamic NPY-ergic activity
Périodique
Endocrine
Auteur(s)
Moreno  G., Perello  M., Gaillard  R. C., Spinedi  E.
ISSN
0969-711X (Print)
Statut éditorial
Publié
Date de publication
03/2005
Volume
26
Numéro
2
Pages
99-106
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Mar
Résumé
Neonatal monosodium L-glutamate (MSG) treatment destroys hypothalamic arcuate nucleus neuronal bodies, thus inducing several metabolic abnormalities. As a result, rats develop a phenotype characterized by hyperleptinemia and by impaired NPY but normal preproorexin hypothalamic mRNAs expression. Thus, our study was designed to explore whether hypothalamic effects of orexin A on food intake and glucocorticoid production develop in the absence of full hypothalamic NPY-ergic activity. For this purpose we evaluated, in control and MSG-treated rats, the consequences of intracerebroventricular (icv) orexin A administration on food intake and changes in circulating levels of ACTH and glucocorticoid. Our results indicate that orexin A icv treatment stimulated hypothalamic-pituitary-adrenal (HPA) axis activity in both MSG-damaged and normal animals, with this response even more pronounced in neurotoxin-damaged rats. Conversely, food intake was only enhanced by icv orexin A injection in normal rats. Our study further supports that acute hypothalamic effects of orexin A on food intake and glucocorticoid production are due to independent neuronal systems. While intact arcuate nucleus activity is needed for the orexinergic effect induced by icv orexin A administration, conversely, orexin A-stimulated HPA axis function takes place even in the absence of full NPY-ergic activity.
Mots-clé
Adrenocorticotropic Hormone/blood Animals Body Weight/physiology Corticosterone/blood Eating/*drug effects/physiology Female Food Deprivation/physiology Hypothalamo-Hypophyseal System/*drug effects/physiology Intracellular Signaling Peptides and Proteins/*pharmacology Leptin/blood Neuropeptide Y/genetics/*physiology Neuropeptides/*pharmacology Pituitary-Adrenal System/*drug effects/physiology RNA, Messenger/biosynthesis/genetics Rats Rats, Sprague-Dawley Reverse Transcriptase Polymerase Chain Reaction Sodium Glutamate/pharmacology Statistics, Nonparametric
Pubmed
Web of science
Création de la notice
15/02/2008 17:57
Dernière modification de la notice
03/03/2018 18:33
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