Ghrelin/GHS-R1a Signaling Modulates Emotional Learning and Memory

Author(s): Nan Li

The amygdala complex is strongly involved in the formation of emotional memories, and GHS-R1a was found to be highly expressed in the lateral amygdala versus the central nucleus. Our previous study showed that micro-injection of ghrelin, the natural ligand of GHS-R1a, into lateral amygdala impairs memory in mice. Consistently, GHS-R1a KO mice shows enhanced memory. To explore the cellular mechanism mediating the effect of GHS-R1a signaling on emotional memory, we recorded spontaneous IPSCs and EPSCs in GHS-R1a KO and WT BL6 control mice. We found that GHS-R1a KO mice exhibited higher amplitude of IPSCs compared to that of control mice, while the EPSC We found that GHS-R1a KO mice exhibited higher frequency compared to that of control mice.

Ghrelin, GHS-R1a, emotional learning, emotional memory

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