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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Pharmacological Manipulation of Immune-Induced Food Aversion in Rats

Texto completo
Autor(es):
Zarzana, Eduardo C. [1] ; Basso, Alexandre S. [1] ; Costa-Pinto, Frederico A. [1] ; Palermo-Neto, Joao [1]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Sch Vet Med, Dept Pathol, Lab Pharmacol & Toxicol, Sao Paulo - Brazil
Número total de Afiliações: 1
Tipo de documento: Artigo Científico
Fonte: NEUROIMMUNOMODULATION; v. 16, n. 1, p. 19-27, 2009.
Citações Web of Science: 6
Resumo

Background: Mice allergic to ovalbumin (OVA) avoid drinking a solution containing this antigen. This was interpreted as related to IgE-dependent mast cell degranulation and sensory C fiber activation. Methods: We employed pharmacological manipulation to further investigate the mediators involved in immune-induced food aversion. Results: While nonimmunized rats preferred a sweetened OVA solution, immunized rats avoided it. We also employed a paradigm in which rats are conditioned to drink water for two 10-min sessions a day. Tolerant rats presented lower IgE titers, and this manipulation abrogated food aversion. Dexamethasone (1.0 mg/kg) prevented the aversion of OVA-immunized rats to the antigen-containing solution. Combined blockade of H(1) and 5-hydroxytryptamine (5-HT)(2) receptors by promethazine (3.0 mg/kg) plus methysergide (5.0 mg/kg) was unable to alter food aversion. Blockade of 5-HT(3) receptors by ondansetron (1.0 mg/kg) caused a twofold increase in the ingestion of the sweetened OVA solution by immunized rats, suggesting the involvement of 5-HT(3) receptors in food aversion. Finally, we showed that dexamethasone or promethazine plus methysergide, but not ondansetron, effectively prevented the IgE-dependent mast-cell-degranulation-induced increase in vascular permeability in rats. Conclusion: We suggest that regardless of whether or not they cause edema, IgE-mediated mast cell degranulation and consequent 5-HT(3) signaling are involved in the process that triggers avoidance to the source of the allergen in allergic rats. Copyright (C) 2008 S. Karger AG, Basel (AU)

Processo FAPESP: 04/14128-0 - Neuroimunomodulação: efeitos do estresse e de citocinas nas relações bidirecionais entre os sistemas nervosos central e imune
Beneficiário:João Palermo Neto
Modalidade de apoio: Auxílio à Pesquisa - Temático