Send to

Choose Destination
Peptides. 2011 Nov;32(11):2248-55. doi: 10.1016/j.peptides.2011.05.014. Epub 2011 May 17.

Central mechanisms involved in the orexigenic actions of ghrelin.

Author information

Department of Physiology, Monash University, Clayton, Victoria 3183, Australia.


Ghrelin is a stomach hormone, secreted into the bloodstream, that initiates food intake by activating NPY/AgRP neurons in the hypothalamic acruate nucleus. This review focuses on recent evidence that details the mechanisms through which ghrelin activate receptors on NPY neurons and downstream signaling within NPY neurons. The downstream signaling involves a novel CaMKK-AMPK-CPT1-UCP2 pathway that enhances mitochondrial efficiency and buffers reactive oxygen species in order to maintain an appropriate firing response in NPY. Recent evidence that shows metabolic status affects ghrelin signaling in NPY is also described. In particular, ghrelin does not activate NPY neurons in diet-induced obese mice and ghrelin does not increase food intake. The potential mechanisms and implications of ghrelin resistance are discussed.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center