[PDF][PDF] Medullary reticular neurons mediate neuropeptide Y-induced metabolic inhibition and mastication

Y Nakamura, Y Yanagawa, SF Morrison, K Nakamura - Cell Metabolism, 2017 - cell.com
Cell Metabolism, 2017cell.com
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 …
Summary
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.
cell.com