Differential role of the hippocampus, amygdala and dorsal raphe nucleus in regulating feeding, memory and anxiety-like behavioral responses to Ghrelin.

VALERIA CARLINI; MARIANA VARAS,; ANDREA CRAGNOLINI,; HELGUI SCHIÜOTH; TERESA SCIMONELLI,; SUSANA RUBIALES,; VALERIA PAOLA CARLINI

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS

Elsevier Inc.

Año: 2004 vol. 313 p. 635 - 635

0006-291X

font face="AdvPSTim-B" size="1"> Abstract Ghrelin is a peptide hormone produced and secreted from the stomach. Hypothalamic injection of the peptide increases food intake but it is not known if the peptide affects other brain regions. We measured several behavioral parameters such as anxiety (elevated plus maze), memory retention (step down test), and food intake after injections of different doses of the peptide in the hippocampus, amygdala, and dorsal raphe nucleus (DRN). The injection of ghrelin in the hippocampus and DRN significantly and dose dependently increased food intake in relation to controls rats, while injections into the amygdala did not affect the food intake. We also show for the first time that ghrelin clearly and dose dependently increases memory retention in the hippocampus, amygdala, and DRN. Moreover, ghrelin at different potencies induced anxiogenesis in these brain structures while the