Appetite controlled by a cholecystokinin nucleus of the solitary tract to hypothalamus neurocircuit
- University of Aberdeen, United Kingdom
- University of Cambridge, United Kingdom
- Harvard Medical School, United States
- Yale University School of Medicine, United States
Abstract
The nucleus of the solitary tract (NTS) is a key gateway for meal-related signals entering the brain from the periphery. However, the chemical mediators crucial to this process have not been fully elucidated. We reveal that a subset of NTS neurons containing cholecystokinin (CCKNTS) is responsive to nutritional state and that their activation reduces appetite and body weight in mice. Cell-specific anterograde tracing revealed that CCKNTS neurons provide a distinctive innervation of the paraventricular nucleus of the hypothalamus (PVH), with fibers and varicosities in close apposition to a subset of melanocortin-4 receptor (MC4RPVH) cells, which are also responsive to CCK. Optogenetic activation of CCKNTS axon terminals within the PVH reveal the satiating function of CCKNTS neurons to be mediated by a CCKNTS→PVH pathway that also encodes positive valence. These data identify the functional significance of CCKNTS neurons and reveal a sufficient and discrete NTS to hypothalamic circuit controlling appetite.
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Animal experimentation: All experimental procedures were performed in accordance with the UK Animals (Scientific Procedures) Act 1986 (Project License No. 60/4565).
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© 2016, D'Agostino et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Appetite controlled by a cholecystokinin nucleus of the solitary tract to hypothalamus neurocircuit
eLife 5:e12225.
https://doi.org/10.7554/eLife.12225
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