Immune-induced flavor aversion in mice: modification by neonatal capsaicin treatment.
OBJECTIVE
This study was designed to evaluate the role of c-sensitive fibers in the establishment of immune-induced flavor aversion in mice.


METHODS
Mice were treated neonatally with capsaicin in order to destroy c-sensitive fibers; after such treatment, adult animals, immunized or not with ovalbumin, were submitted to a two-bottle preference test, with a choice between water and a sweetened egg white solution.


RESULTS
Neonatal capsaicin treatment was unsuccessful in preventing the development of immune-induced aversion to the sweetened solution containing the antigen. Nonetheless, amongst immunized mice, those which had been previously treated with capsaicin showed a significant increment in the preference for the sweetened egg white solution. Furthermore, our data showed that neonatal capsaicin treatment did not interfere with either IgG1 or IgE production.


CONCLUSIONS
The present results suggest that c-sensitive fibers have a role in the transmission of the signals generated by this immune response to the central nervous system, thus contributing to the development of a flavor aversion in mice.
Basso
A S
AS
Applied Pharmacology and Toxicology Laboratory, Department of Pathology, School of Veterinary Medicine, University of São Paulo, Brazil.
de Sá-Rocha
L C
LC
Palermo-Neto
J
J
D000818:Animals; D000831:Animals, Newborn; D001362:Avoidance Learning; D002211:Capsaicin / Q000494:pharmacology*; D003714:Denervation; D005512:Food Hypersensitivity / Q000276:immunology / Q000503:physiopathology; D005518:Food Preferences / Q000502:physiology; D007073:Immunoglobulin E / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009412:Nerve Fibers / Q000187:drug effects / Q000276:immunology*; D015213:Neuroimmunomodulation / Q000187:drug effects* / Q000502:physiology*; D010047:Ovalbumin / Q000276:immunology; D009435:Synaptic Transmission / Q000276:immunology; D013649:Taste / Q000276:immunology*
D007074:Immunoglobulin G; D007073:Immunoglobulin E; D010047:Ovalbumin; D002211:Capsaicin