Hippocampal Ghreline- containing neurons, modulate food-intake behavior by direct patways to ventrobasal hypothalamus and basolateral amygdala.

Feeding is a complex behavior that is influenced by learned associations between external and internal cues. Ghrelin (Ghre) is considerable stimulatory roles in modulating food intake, Ghre-levels rise in anticipation of food intake based on learned. Hippocampal subregion neurons (H-CA1) constitute an important neural substrate to control both appetitive and ingestive behavior. H-CA1 field also innervates amygdala regions that in turn innervate the hypothalamus. A recent study also implies that Ghre effects on cue-potentiated feeding behavior occur, at the least, via indirect action on the amygdala. In the present study,we investigate on the neural substrates through which endogen Ghre communicates conditioned appetite and feeding behavior within the CNS. We theorize the existence of a neural pathway Ghre dependent whereby peripherally-derived Ghre activates H-CA1glut-pyramidal neurons, which in turn activate ghre-expressing hypothalamic and amygdaloid neurons to stimulate appetite and feeding behaviour. In this study we use two retrograde tracers (FG, DIL) and immunocytochemical detection of Ghre. Triple fluorescent-labelling determine the presence and the distribution of H-CA1Ghre-containing neurons that project to the Hypothalamus and Amygdala. Triple labelled H-CA1 neurons were identified. These results suggest that H-Ghre-containing neurons into fields CA1, modulate food-intake behavior by direct patways to ventrobasal hypothalamus and basolateral amygdala.