Mechanisms of xenin-induced anorectic response in chicks (Gallus gallus).
Gen Comp Endocrinol
; 157(1): 58-62, 2008 May 15.
Article
em En
| MEDLINE
| ID: mdl-18440536
ABSTRACT
We recently reported that the 25 amino acid peptide xenin caused reduced feed intake when centrally injected in chicks. The present study was designed to explore possible mechanisms of the xenin-induced anorexigenic response in chicks. In Experiments 1 and 2, chicks were implanted with cannulas and xenin injections were made directly into the ventromedialis hypothalami (VMH). Chicks responded with reduced feed intake and increased c-Fos immunoreactivity at the VMH. In Experiment 3 chicks that received co-intracerebroventricular (ICV) injection of naloxone and a dose of xenin (100 pmol), that alone does not affect feed intake, had reduced feed intake. In Experiment 4, chicks responded to ICV xenin with reduced feed- but increased exploratory-pecking. Thus, we conclude that xenin may mediate its effect directly at the VMH and that the endogenous opioid system may counter anorexigenic effects of low xenin doses in chicks. Xenin also caused increased exploration of a novel environment, an effect that may be competitive with feeding. Taken together, these results suggest that xenin regulation of chick appetite is the result of several central and behavioral mechanisms acting in synergism.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
/
Anorexia
Limite:
Animals
Idioma:
En
Revista:
Gen Comp Endocrinol
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Estados Unidos