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bioRxiv · 10.1101/2023.01.28.525750

The parasubthalamic nucleus refeeding ensemble delays feeding initiation

Abstract

The parasubthalamic nucleus (PSTN) is responsive to refeeding after food deprivation and PSTN subpopulations can suppress feeding. However, no study directly addressed the role of PSTN neurons activated upon food access resumption. Here we show that the ensemble of refeeding-activated PSTN neurons drastically increases the latency to initiate refeeding with both familiar and novel food but exerts limited control over the amount of food consumed by hungry mice. This ensemble also delays sucrose consumption but accelerates water consumption in thirsty mice. We next sought to identify which subpopulations of PSTN neurons might be driving these effects. We discovered that PSTN Tac1 neurons projecting to the CeA selectively suppress feeding initiation while PSTN Crh neurons surprisingly promote the consumption of novel, palatable substances. Our results demonstrate the key role of endogenous PSTN activity in the control of feeding initiation and identify PSTN subpopulations counteracting each others influence on consummatory behaviors.

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BibTeXRIS

Dunning, J. L., Lopez, C., Krull, C., Kreifeldt, M., Angelo, M., Ramakrishnan, C., Deisseroth, K., Contet, C.. 2023-01-30. The parasubthalamic nucleus refeeding ensemble delays feeding initiation. https://doi.org/10.1101/2023.01.28.525750

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