Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/196923
Type: Artigo de periódico
Title: Circulating Ghrelin Concentrations Are Lowered By Intracerebroventricular Insulin.
Author: Ueno, M
Carvalheira, J B C
Oliveira, R L G S
Velloso, L A
Saad, M J A
Abstract: Ghrelin is a peptide that is mainly produced by the stomach and stimulates food intake, adiposity and weight gain. Previous studies have documented that plasma levels of ghrelin are reduced by insulin, but the mechanisms that mediate this effect are unclear. To determine whether phosphatidylinositol 3-kinase (PI(3)K) and/or mitogen-activated protein kinase (MAPK) are involved in this insulin action, we tested the intracerebroventricular (i.c.v.) effect of specific inhibitors of PI(3)K (LY294002 and wortmannin) and MAPK (PD98059 and UO126) on the insulin-mediated reduction of ghrelin levels in rats. Intracerebroventricular treatment with insulin reduced ghrelin levels. Inhibition of PI(3)K specifically blocked the insulin-induced reduction in ghrelin concentration, whereas inhibition of MAPK had no effect on insulin-mediated actions. Moreover, pretreatment with i.c.v. PI(3)K inhibitors blocked the reduction of ghrelin levels after OGTT-induced hyperglycaemia and hyperinsulinaemia. These data demonstrate that changes in insulin action in the central nervous system regulate circulating ghrelin levels and that PI(3)K is a specific mediator of this action.
Subject: Animals
Food Deprivation
Ghrelin
Hypothalamus
Injections, Intraventricular
Insulin
Kinetics
Mitogen-activated Protein Kinases
Peptide Hormones
Phosphatidylinositol 3-kinases
Rats
Rights: fechado
Identifier DOI: 10.1007/s00125-006-0371-8
Address: http://www.ncbi.nlm.nih.gov/pubmed/16955211
Date Issue: 2006
Appears in Collections:Artigos e Materiais de Revistas Científicas - Unicamp

Files in This Item:
File SizeFormat 
pmed_16955211.pdf177.6 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.