Abstract
Hypothalamic neuropeptide Y (NPY) elicits hunger responses to increase the chances of surviving starvation: an inhibition of metabolism and an increase in feeding. Here we elucidate a key central circuit mechanism through which hypothalamic NPY signals drive these hunger responses. GABAergic neurons in the intermediate and parvicellular reticular nuclei (IRt/PCRt) of the medulla oblongata, which are activated by NPY-triggered neural signaling from the hypothalamus, potentially through the nucleus tractus solitarius, mediate the NPY-induced inhibition of metabolic thermogenesis in brown adipose tissue (BAT) via their innervation of BAT sympathetic premotor neurons. Intriguingly, the GABAergic IRt/PCRt neurons innervating the BAT sympathetic premotor region also innervate the masticatory motor region, and stimulation of the IRt/PCRt elicits mastication and increases feeding as well as inhibits BAT thermogenesis. These results indicate that GABAergic IRt/PCRt neurons mediate hypothalamus-derived hunger signaling by coordinating both autonomic and feeding motor systems to reduce energy expenditure and to promote feeding.
Original language | English (US) |
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Pages (from-to) | 322-334 |
Number of pages | 13 |
Journal | Cell Metabolism |
Volume | 25 |
Issue number | 2 |
DOIs | |
State | Published - Feb 7 2017 |
Keywords
- brown adipose tissue
- cardiovascular
- feeding
- hunger
- medulla
- metabolism
- neural circuit
- obesity
- sympathetic
- thermoregulation
ASJC Scopus subject areas
- Physiology
- Molecular Biology
- Cell Biology