Ghrelin is an recently discovered peptide hormones that play opposite roles in the food intake, body-weight control and energy homeostasis in both human and rodents. Beyond its appetite-control function, increasing evidence has shown that ghrelin affects multiple advanced activities in the central nervous system, including memory and emotion. However, the possible actions of ghrelin in those important brain regions are largely unknown. In this study, we micro-infused ghrelin into the lateral amygdala (LA) or area CA1 of the dorsal hippocampus (CA1) and investigated the immediate effects of those two peptide hormones on cognitive and affective behaviors. We found that the micro infusion of ghrelin into the LA or the CA1 interfered with certain types of learning and memory in both rats and mice. Our data thus suggested that ghrelin affects learning and memory.
Ghrelin, GHS-R1a, Amygdala, Hippocampus, Memory
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